Are Changes Brewing and How Does the Mind Fit In?
by BradfordSometimes plugs can be appreciated by more than plumbers. I found this to be the case with NEW PHYSICS AND THE MIND. There are attention grabbing comments like this one:
The mind has played a role in physics since the earliest days of quantum physics. The Fifth Solvay Conference in 1927 featured a debate between Niels Bohr and Albert Einstein about whether the mind and consciousness are (Bohr) or are not (Einstein) part of physics. Einstein's position has dominated mainstream physics for decades, but the battle simmered on for the entire twentieth century.
And questions like these:
How many phenomena of new physics does it take to break the standard model?
Are we really getting closer to a theory of everything by reducing our understanding to strings as physics' smallest pieces?
Can psychologists', mathematicians', and physicists' longstanding p-adic models of thought be brought into modern physics?
What optimal mix of new physics phenomena and p-adic models of consciousness have created holistic models of new physics and the mind, the 21st century's theory of everything?
Raw meat for a crowd of TT commenters with answers.
February 12th, 2008 at 12:11 pm
Bradford:
LOL!!! But I'm a vegetarian, Bradford!
But yeah, I've been following Matti's always expanding theoretical applications for a decade. Which doesn't mean I understand the details, of course. Using p-adic mathematics does get around some issues with the inventive (but not necessarily revealing) 'standard' maths with imaginary, irrational and all other sort of made-up numbers/values. The p-adic primes themselves encompass infinities that have served to distort more standard ToEs (and have to be factored out by fiat via "renormalization"). Which even the brightest mathematicians admit is cheating.
Anyway, Matti's blog is TGD Diary. Now I'm going to have to look at Sidharth's quantum black holes (an idea I encountered back in the '70s but generally rejected by gatekeepers due to implications) too. Must put Paster's book on my wish list.
< sigh > When will I ever win that darned lottery I don't play, so I can afford stuff I want? §;o)
Comment by Joy — February 12, 2008 @ 12:11 pm
February 12th, 2008 at 12:33 pm
Joy:
I'm at the part of the learning curve reserved for beginers when it comes to quantum physics and its relationship to issues discussed at TT. Nevertheless it is intriguing. It looks like you are in the Niels Bohr camp with regard to whether the mind and consciousness are part of physics. Would that be accurate?
Comment by Bradford — February 12, 2008 @ 12:33 pm
February 12th, 2008 at 3:09 pm
Here are some comments that I made last summer that I think are relevant here:
David Chalmers wrote in his book, The Conscious Mind, that
(p101,102)
In his essay "Remarks on the Mind-Body Question" Nobel laureate Eugene Wigner writes: "it is not possible to formulate the laws of quantum mechanics [QM] in a fully consistent way without reference of the consciousness."
Expanding on the implications of Wigner's remarks, Harold Morowitz comments that it is remarkable that the scientific study QM has led to the revival of the concept of "consciousness as an ultimate reality." ("Reducing the Mind," Psychology Today, Aug 1980) This I think explains why many of the researchers of consciousness (Chalmers & Searle, for example) spend a lot of time focusing on the ontology of consciousness. Ontology, which is sometime used interchangeably with the term metaphysics, is simply a way to try to conceptualize what something really is at its most basic, fundamental or essential level.
The irony of all this is that the concept of mind and consciousness as ontologically distinct and irreducible has come out of modern physics, which in the 19th century was, without a doubt, the most reductionistic of the physical sciences.
Morowitz comments: "The founders of modern atomic theory did not start out to impose a mentalist picture on the world. Rather, they began with the opposite point of view and were forced to the present day position in order to explain experimental results."
I really like the way Morowitz concludes his article. He says that "a forceful commitment to uncritical reductionism as a solution to the problem of the mind"¦ is a dangerous view, since the way we respond to our fellow human beings is dependent on the way we conceptualize them in our theoretical foundations. If we envision our fellows solely as animals or machines, we drain our interaction of humanistic richness. If we seek our behavioral norms in the study of animal societies, we ignore those uniquely human features that so enrich our lives. Radical reductionism offers very little in the area of moral imperatives."
The bottom line, at least for the present, is that it is conceptually easier (more parsimonious) simply to conceive of mind and consciousness as a fundamental aspect of reality rather than something that emerges out of (or can be reduced to) something else. So far, at least for the present, it is the best explanation for the collapse of the wave function that has been well established in experimental studies. Any other explanation has to invoke new non-empirical (metaphysical) constructs: many worlds, retrocausality etc.
Comment by JOHN_A_DESIGNER — February 12, 2008 @ 3:09 pm
February 12th, 2008 at 4:16 pm
Thanks for comment John. I've been pondering a post on the subject and if I get to it your information will be helpful.
Comment by Bradford — February 12, 2008 @ 4:16 pm
February 12th, 2008 at 5:04 pm
Electricians, for instance?
Comment by The Pixie — February 12, 2008 @ 5:04 pm
February 12th, 2008 at 5:11 pm
Bradford:
Hahaha!!! Oh, heavens no! I struggle to wrap my head around stuff just like everybody else (it makes me cross-eyed!). I struggled with TGD for years before finally shrugging and taking Matti's word for it.
Though I do have some past experience in the fields of nuclear and particle physics. I desire "real answers." I like unexpected things too, have managed to encounter enough to keep me from believing too much in standard models of the ordinary. The anomalous is more surprising – thus often a lot more interesting – than the normal and mundane.
Came to the conclusion decades ago that any wannabe theory of everything that couldn't account for the anomalous as well as the mundane was probably not worth believing in. Anomalous things happen all the time. As if… as if what we consider normal and mundane (the things wannabe ToEs claim to explain) are really just habits of matter and energy that have nothing to do with "laws."
Comment by Joy — February 12, 2008 @ 5:11 pm
February 12th, 2008 at 5:18 pm
Electricians, metaphysicians et. al. Some of the smartest people in America write ads. Maybe that explains some things.
Comment by Bradford — February 12, 2008 @ 5:18 pm
February 12th, 2008 at 5:21 pm
Hi Bradford,
You asked Joy…
Let me give you my reader's digest version.
The 1994 debate between Penrose and Hawking was thought to be the modern version of the debates between Bohr and Einstein.
Penrose is on the same side of the QM schism as Bohr was.
Hameroff/Penrose model of consciousness is on the same side of the schism as Bohr was.
Joy was the one who introduced me to the Orch OR model of consciousness.
The interesting part is examining those opposing the Bohr/Penrose view.
Hawking takes the position that deciding what is real or not is not needed to do science. Anything that predicts experimental data is good enough.
There is the Many Worlds interpretation that, to me, comes across as a last ditch effort to hang on to particles and materialism.
With Penrose, everything is part of one giant wavefunction.
Orch OR suggests our consciousness is interconnected with this universal wavefunction.
Note, I am still reluctant to overly dwell on implications that might suggest the existence of a universal consciousness.
I have a reputation to maintain, so keep it quiet, ok?
Comment by Thought Provoker — February 12, 2008 @ 5:21 pm
February 13th, 2008 at 1:16 am
John_A:
QM doesn't really require anybody to believe that wavefunctions collapse. And many quantum physicists (theoretical and experimental) don't bother. It's not necessary to consider any of the beasties in the zoo to be "real." If we knew more about time we could probably decide one way or the other. Unfortunately, we don't know much about time.
Comment by Joy — February 13, 2008 @ 1:16 am
February 13th, 2008 at 1:25 am
TP:
Ahhh… didn't catch that meaning from Bradford's question. Just scanning the material, had work to do.
Orch-OR is an excellent door-opener. It will do way more than Matti's TGD (or Sidharth's quantum holes) to get the gummed-up physics works unstuck for the 21st century. Roger Penrose is a much nicer guy than Isaac Newton ever was, with the same kind of serious clout. I can't think of anyone better to open this door, show the more skeptical gatekeepers who fear what's on the other side that fear is never going to give physics the future it wants and needs.
At least it makes of consciousness a real consideration. It's been there for a hundred years, it's just that few really wanted to take it seriously. So long as the math 'worked' FAPP, nobody had to choose which side of the fence to graze (as a matter of science). Belief-in is a philosophical preference, nothing more scientific than that. Then we got the technology to test at at higher energy levels, and the math started spewing nonsense.
I'm a realist, FAPP. That doesn't mean I must believe-in Copenhagen or many worlds or any versions thereof. I don't have to believe all the beasties are "real," I never saw any conclusive evidence that they are. We don't "see" any of them, we observe the past-time tracks of their interactions. All anybody need accept is that something's interacting. "Gauge fields" of one variety or another, carrying forces of one sort or another. The interactions are complex as hell. They appear to enjoy extra degrees of freedom at scales of quantum and sub-quantum forces.
Extra degrees of freedom are basically extra dimensions. It's all real enough, FAPP. The universe moves on, the wavefunction's continual awareness of itself ticking moment to moment (whatever those are). Did I ever link you to Paola Zizzi's "Big Wow" theory? I think it's linked from Hameroff's page…
"A funny thing happened on the way to vector alignment" might be a good tale to tell someday. It never really has to collapse to a single vector – I don't think it can (unless we get an unwelcome universal phase transition like the Brookhaven critics pointed out was possible). It's all going to be dynamically balanced on the edge of chaos. "Always" being another FAPP term, depending again on what time turns out to be.
Guess what I'm saying is that there aren't just two ways to view reality – either a static "is-ness" of frozen real objects blurred by scale (and time) or a proliferating plethora of alternative realities self-generating ad infinitum (in time). It can be a process. That's why I like the multi-stage collapse notion. It can go on forever, or close enough in the 4-D world.
Consciousness can be fundamental to manifestation. It need not be reducible to or emergent from it.
Comment by Joy — February 13, 2008 @ 1:25 am
February 13th, 2008 at 8:27 am
John
How do you figure it is more parsimonious to introduce an entirely quantity into our explanation of the universe as opposed to a quantity emerging from what we already know about. I would have said the reverse.
I thought you were invoking a new non-empirical construct too with this fundamental aspect of reality. Or do you have empirical evidence that consciousness is like that?
TP
How do you decide what is real?
Comment by The Pixie — February 13, 2008 @ 8:27 am
February 13th, 2008 at 1:14 pm
Joy:
Whether or not it does or doesn't is irrelevant what happened historically in theoretical Physics. There are no doubt that historically the implications of what was really going on with waves/particles revived an interest among physicists in questions about mind and consciousness. But, I agree that some of the speculations that arise out of QM are somewhat over reaching, if not out right fanciful.
For example, in his book, The Mystery of Consciousness, John Searle makes a critique of theories of consciousness based on QM, in particular Penrose's hypothesis. He writes:
""¦at this point any account of consciousness is bound to contain speculative elements. The problem with these speculations is that they do not adequately speculate on how it is even conceivable that we might solve the problem of consciousness. They are of the form: if we had a better theory of quantum mechanics and if that theory were noncomputable then maybe we could account for consciousness in a noncomputational way. But how? It is not enough to say that the mystery of consciousness might be solved if we had a quantum mechanics even more mysterious than the present one. How could it possibly work? What are the causal connections supposed to be?"
Physicist Richard Feyman once said, "anyone who claims to understand quantum theory is either lying or crazy." Penrose and Hameroff, for example, have developed an explanation for consciousness based on our current understanding of quantum mechanics; however, their hypothesis at present, in my opinion, is little more than using one kind of mystery (QM) to explain another (consciousness). In reality all you end up with are two mysteries instead of one. How crazy is that?
Comment by JOHN_A_DESIGNER — February 13, 2008 @ 1:14 pm
February 13th, 2008 at 3:18 pm
Pixie, you asked:
You're not a conscious, intelligent being? Do you know that you are conscious and intelligent? How can you say that consciousness is something we don't know something about? Think man, just think.
Have you read any ancient philosophy? My reading of Plato, Aristotle et al. is that they were talking about the mind 2000+ years ago. How can you describe that as new? My point was that those seeking to explain the collapse of the wave function, apart from the role of a conscious observer, often turn to equally "metaphysical" explanations. These are relatively new.
Comment by JOHN_A_DESIGNER — February 13, 2008 @ 3:18 pm
February 13th, 2008 at 4:29 pm
John_A:
Yeah, well. What does "understand" mean in this instance? I figure if you can work the equation – "the math works!" – that's all the understanding you need. At least, it's all you need to be a quantum physicist. What more does anybody expect?
Interpretations to metaphysical philosophies and a priori beliefs are entirely superfluous and don't (never did) count as science. I thought we all 'understood' that.
Deal is – and it's a bit of a big deal – the math no longer works. It spews nonsense at high energy scales, "everybody knows" the theory's wrong. They've been looking for a replacement for more than 30 years. It's not going to come out of nowhere, and it's probably going to have to consider that consciousness link they couldn't successfully ignore for the whole last century. That's the breaks.
Not crazy at all. QM isn't a mystery, it's the mathematical description of how the whole thing works once the reductionists have reduced it to where they can't possibly reduce it any further. They asked for it, they got it. Why complain now?
Consciousness isn't a mystery either, even though people who appear to be conscious like to pretend it is. It's real – a simple fact of life – and we all empirically experience it directly. We may not be able to explain it adequately, but that doesn't mean it doesn't exist or isn't the realest thing human beings ever encounter empirically in their lifetimes. Lots of words are misapplied whenever someone wants to obfuscate or avoid dealing with what's right there on top of the table for all to see. A quirk of consciousness, nothing more.
Comment by Joy — February 13, 2008 @ 4:29 pm
February 14th, 2008 at 6:53 am
John
Of course I think I am conscious and intelligent. What did I write that might suggest otherwise? And where did I say that consciousness is something we don't know something about? Read man, just read! And then think.
You are making the specific claim that consciousness is "a fundamental aspect of reality", and that this is the more parsimonious explanation. That is what I challenge, not the existence of consciousness.
Okay, scratch that. How about "unknown" instead. So now you are invoking an unknown non-empirical construct with this fundamental aspect of reality, and yet claiming parsimony (unless you have empirical evidence that consciousness is a fundamental aspect of reality).
Comment by The Pixie — February 14, 2008 @ 6:53 am
February 14th, 2008 at 3:27 pm
Pixie:
Let me briefly state my POV:
In my opinion, there are 3 major questions that any kind of naturalism or materialism cannot presently resolve:
1. What is the cause of the universe?
2. What is the cause of life?
3. What is the cause of mind and consciousness?
At least "˜classical atheism' as espoused by Bertrand Russell and others seemed to be somewhat reasonable. One could attribute aseity or "˜self-existence' to space-time, matter-energy and the universe as a whole. If the universe was infinite and eternal it could be then argued that it is the cause of all finite and contingent being; or perhaps more accurately all that has ever existed is an eternal regress of natural causes. It appears; however, that the "˜Big Bang' has caused something of a metaphysical bottleneck that limits this kind of natural causal nexus. Whatever caused the universe, it now appears, must, at least, in some sense transcend the universe both spatially and temporally. An infinite regress is no longer an easy, simple, or adequate explanation. It can no longer be argued that matter and energy are eternal. What caused or existed before the universe is, at least for the present, appears to be empirically an open question.
The simpler and, in my view, better explanation is that a mind or intelligence is the self-existing (or ontologically self-contained) thing that transcends the universe. It exists because it has always existed. It's not much more complicated than that. I think Billy Ockham would have been pleased.
David Chalmers in his book, The Conscious Mind, argues that consciousness can be conceived of ontologically the same way that we conceive of space-time and matter- energy; as something that is ontologically, or conceptually, irreducible and basic. However, I part company with Chalmers when he starts speculating about pan psychism. I don't think thermostats or toasters are conscious.
On the other hand, the result of experiments like the classic double slit experiment strongly suggest that consciousness plays a fundamental role in our understanding of physical systems at their most basic level. It appears, for example, that conscious observation has an effect on subatomic particles (causes the collapse of the wave function, for example) and, furthermore, this property appears to a property of matter that existed even before conscious beings (animals, people and ET's?)existed. Many modern physicists are absolutely convinced of this.
Once again to quote Morowitz: "The founders of modern atomic theory did not start out to impose a mentalist picture on the world. Rather, they began with the opposite point of view and were forced to the present day position in order to explain experimental results."
Comment by JOHN_A_DESIGNER — February 14, 2008 @ 3:27 pm
February 14th, 2008 at 4:05 pm
JAD:
Sounds like nonsense to me. So before conscious beings existed, what caused wave function collapse? Can we detect consciousness this way? "Aha, the wave function didn't collapse, she must be unconscious."
Comment by Raevmo — February 14, 2008 @ 4:05 pm
February 14th, 2008 at 7:56 pm
Raevmo to John:
As I mentioned, it doesn't have to (finally) collapse if more than 4 dimensions are involved. Sort of a post-Bohmian view with de Broglie overtones – an ongoing incremental phase transition or vector alignment, depending on whether you're talking wave or particle behaviors. The choice to talk about waves or particles determines the labels, just as the choice of which to measure determines the form.
Much of high-end theoretics in particle physics (under the umbrella of RQFT), does grudgingly accept the Aspect falsification of Bell's inequality theorem – thus the actuality of quantum non-locality (a.k.a. entanglement). They've formulated the idea of instantaneous exchange of force particles – hidden variables – that lets them salvage belief-in determinism. Naming them doesn't make them any less hidden, it just lets them talk about their hidden variables as if they were in plain sight.
The non-deterministic aspects of quantum mechanics don't make it an "incomplete theory." Reality might just be that way, and the hidden variable (or one of them) might be consciousness. It could be that the interpretations of quantum mechanics make it seem incomplete. There may be no final collapsed state and no infinitely self-generating multiverse – just an ongoing process and relative degrees of ability to consciously experience and control it.
So it sure seems premature to rule out the existence of such mechanism(s) at this stage of the investigation, and even more premature to rule out the existence of a fundamental (parameter, force or law) that expresses through a mechanism.
Comment by Joy — February 14, 2008 @ 7:56 pm
February 15th, 2008 at 7:31 am
Hi John
Oh to be a theologist, and you can answer al the hard questions with "God did it".
What changed that caused this eternal intelligence to create the universe? It had already existed for eternity; why the sudden desire to create a universe? Bear in mind that by the time of the Big Bang this eternal intelligence had already had an infinite number of thoughts. It must have reached the decision to create the universe an infinite number of times before it actually did so – or not at all. There is a problem with the infinite creating the finite.
Can you talk me though this. Thinking about Schrodinger's cat (radioactive decay -> detector -> poison -> cat -> observer), why do you think wave collapse does not happen at the detector or with the cat? If consciousness is a fundamental property of nature, then why should we not think the cat is conscious? Suppose we use an ant instead of a cat, is that conscious enough to collapse wavefunctions? How about a mushroom? How about that detector again? At what point is an embryo/foetus/baby/child conscious enough to effect quantum collapse? Is there a sudden event when a baby becomes conscious? Are there any observations that might support that claim? The whole idea that consciousness causes quantum collapse raises a whole raft of new quiestions. That does not make it wrong, but claims of parsimony seem unjustified.
So in what sense is this property the same as what you or I know as consciousness? For me consciousness implies subjectivity and awareness, and I cannot see how that can be true of a property of matter that predates animals. You seem to be arguing that consciousness is required for quantum collapse, but conscious beings are not, which appears to be an inherent contradiction. If you do not need conscious beings for quantum collapse, that would suggest – going back to Schrodinger's cat – that it could well happen at the detector. So now we have eliminated consciousness from the experiment!
Comment by The Pixie — February 15, 2008 @ 7:31 am
February 15th, 2008 at 7:40 am
Or simply be someone who is honest enough to admit that science has limits which do not allow for empirical resolutions of the questions posed.
Comment by Bradford — February 15, 2008 @ 7:40 am
February 15th, 2008 at 8:37 am
I will happily admit that science may not be able to answer the questions. How can you be so (dogmatically) sure it cannot?
Comment by The Pixie — February 15, 2008 @ 8:37 am
February 15th, 2008 at 10:45 am
Hi Pixie,
While I would tend to agree with your general assessment of Bradford's stubbornness, in this case Bradford did add the qualifier "presently".
For what it is worth.
P.S. I just noticed Bradford said "…science has limits which do not allow for empirical resolutions".
I should get back to work.
Comment by Thought Provoker — February 15, 2008 @ 10:45 am
February 15th, 2008 at 1:52 pm
Pixie wrote:
Name me a modern theologian (theologist?) other than some screwball fundamentalist who answers the "hard questions" with "God did it" Is that something you actually heard or read or is it the way you think theologians, and people like me who are interested in theology, think?
Consider this quote by John Gribbin from his book, In Search of Schrodinger's Cat:
Gribben goes on in the next chapter to describe the Many Worlds Interpretation. This is the one that he apparently prefers.
Notice how Gribben begins: "By definition, the universe is self-contained. It includes everything, so there is no outside observer who notices the universe and therefore collapses its web of inter-acting alterative realities into one wave function." But consider another possibility. There is an eternally existing omniscient outside observer. Wouldn't that solve many of the issues that Gribben has raised? In my mind it would also be a more parsimonious answer.
BTW I don't know whether or not this particular interpretation is correct but scientists like Gribben do. He writes: "So not only is the Copenhagen interpretation fully vindicated for all practical purposes by experiments, it looks as if there are developments in store far beyond those that quantum mechanics has already given us"¦'
As Joy has pointed out there are other ways to look at this puzzle.
Comment by JOHN_A_DESIGNER — February 15, 2008 @ 1:52 pm
February 15th, 2008 at 2:12 pm
TP:
Remember my concept of scientific limits TP. The limit of science is determined by reliable predictions that flow from it. Reliability can vary with time.
Comment by Bradford — February 15, 2008 @ 2:12 pm
February 15th, 2008 at 4:47 pm
Pixie wrote:
You seem to be trying to make an argument similar to the Kalam cosmological argument championed by William Lane Craig. His argument can be summarized as follows:
1. An actual infinite cannot exist.
2. A beginningless series of events is an actual infinite
3. Therefore, the universe cannot have existed infinitely in the past, as that would be a beginningless series of events.
I have always thought this was a somewhat superfluous argument. I realize that when we consider something like infinity we run into all kinds of paradoxes, both mathematical and metaphysical. But what is the alternative? That the universe just began without a cause? Something came from nothing uncaused? To me that way of thinking is more problematic than the paradoxes caused the idea of an actual infinity.
Craig runs into a problem when he tries to argue against a temporal infinity but the tries to reintroduce the concept of an ontological infinity, God, who is the cause of both space and time. But then, maybe I don't really understand his argument.
Frankly, in my opinion, the finite human mind simply cannot comprehend the infinite. However, I can comprehend the idea that as far back as I can think in time I can conceive of something existing before that. Furthermore, an always existing something is not only a rational concept it is an ontologically basic one. It's nonsense to ask what existed before an always something. The answer is obvious. Nothing.
Comment by JOHN_A_DESIGNER — February 15, 2008 @ 4:47 pm
February 15th, 2008 at 7:53 pm
John
Ah, I should have said theist. Yes, I am sure a theologian who want more of an answer. So now I am curious. Do you think theologian can presently resolve those three questions? The way yopu said "In my opinion, there are 3 major questions that any kind of naturalism or materialism cannot presently resolve" suggests you believe other philosophies can resolve those questions. Why single out naturalism or materialism otherwise?
No, invoking a new, unknown entity is the antithesis of parsimony!
And if we go back to Schodinger's cat, you are again removing the quantum collapse from the (mortal) observer. You seem to start by claiming that quantum collapse is caused by the conscious observer, and end up saying actually it is not!
Sure, I have my favourite, but it is all up in the air.
Well, yes, we just using it to prove opposites.
I have no problem with that. There is some evidence that the universe adds up to nothing – negative and positive charges cancel each other, matter and anti-matter cancel, negative (potential) energy cancels positive energy. Maybe the universe is an example of nothing coming from nothing. Quantum fluctuations are a known example of an uncaused effect. So, yes, a universe without a cause coming from nothing.
Comment by The Pixie — February 15, 2008 @ 7:53 pm
February 16th, 2008 at 12:10 pm
Pixie,
Aren't you then invoking an unknown? How could you ever prove to skeptic like me that the universe came into being uncaused from nothing? Lot of things are possible; for example there is nothing impossible about the idea that unicorns really exist. But to believe that they really exist without any evidence requires a leap of faith. Other ideas like 5 + 11=17 are assertible or sayable but unprovable. They require a leap of both faith and logic. IOW there is no possible world where 5 + 11=17. IMO your claim that something can come into existence uncaused from absolute nothing falls into this latter category.
Comment by JOHN_A_DESIGNER — February 16, 2008 @ 12:10 pm
February 16th, 2008 at 12:52 pm
Mere desperation, John. We all choose what to believe. An uncaused universe of nothing coming from nothing for no reason is no doubt comforting to some (narcissists, nihilists, maybe some other 'ism' out there). But one could legitimately wonder how come they want everybody else to believe it too, since it makes no sense at all.
Comment by Joy — February 16, 2008 @ 12:52 pm
February 16th, 2008 at 1:32 pm
Hi John Designer,
I'll apologize up front for beating my OMA/NOMA drum again but it goes right to the point, IMO.
Unlike Theism, Atheism doesn't lend itself to an absolute statement. Even Dawkins admits it is possible God exists (just as it is possible fairies exist at the bottom of gardens).
Once a theist decides God absolutely does exists (for whatever reason) then if he/she embraces OMA, the game is over. GodDidIt is the simplest scientific explanation for all things.
However, if a theist like Ken Miller embraces NOMA, then scientific exploration can continue as it has.
Logical arguments can be made that a complete explanation is unknowable. Not just forever unknown, but actually unknowable (see Kurt Gödel)
If you insist on rejecting NOMA, we can have a very lively discussion on your logic and proof for your single, OMA Truth for us all, but don't expect special treatment for religious beliefs.
If you embrace NOMA, we can still have a lively scientific discussion along with lively philosophical discussions but agree to keep them separated and respect that no one knows the Truth.
Comment by Thought Provoker — February 16, 2008 @ 1:32 pm
February 16th, 2008 at 1:52 pm
TP:
God did it is no more scientific than natural forces did it. There is a lack of causal specificity in both statements. IDists share this much in common with Dawkins. Both sides believe scientific data can be used to support their respective beliefs. When you write "Even Dawkins admits it is possible God exists" you are noting a throw away line used to shore up one's backside from logical assaults. He may say that but everyone knows he no more allows for its possibility than the apostle Paul allowed for Christianity being a sham. In Paul's case he wrote somewhere in the NT that (paraphrasing) if Christ did not rise from the dead then our faith is useless and we are the most pathetic of people. He used the conditional which one could argue (like Dawkins) allows for the possibility. Incidentally if you wish to stoke the culture war flames keep inserting those fairy comments. You're sending the clear (although somewhat camoflauged message) that our metaphysics is more real than yours.
Comment by Bradford — February 16, 2008 @ 1:52 pm
February 16th, 2008 at 2:45 pm
Hi Bradford,
Your reaction is interesting on multiple levels, starting with the appearance the you are violently agreeing with my point.
Faries existing at the bottom of gardens came from Dawkins' book which is why I mentioned it when discussing Dawkins' stated position.
Dawkins rejects NOMA loudly and clearly. As you indicated, it is obvious the ID Movement also rejects NOMA.
At least until political and legal ramifications start to come into play.
Walt Brown (see http://www.creationscience.com) rejects NOMA and is clearly trying to use scientific data in support of his belief.
If you want to do the same thing, great. Shield bash all you want. Yell and scream that science is incapable of solving the OOL puzzle. You can even refuse to suggest mechanisms and hypotheses.
However, don't be surprised when people don't take you seriously if and when you try to claim your version of ID is not about religion, because it's apparent that it is.
It is obvious you believe your "metaphysics is more real" than mine because, philosophically, I believe I don't know the Truth.
Comment by Thought Provoker — February 16, 2008 @ 2:45 pm
February 16th, 2008 at 5:05 pm
Distinguish between shield bashing and warring for your cultural side.
You can discount something I say about OOL or any other scientifically linked topic when I delink my arguments from scientific data. Until then my biases no more negate my views than do the biases of PZ Myers and Dawkins negate theirs.
Comment by Bradford — February 16, 2008 @ 5:05 pm
February 16th, 2008 at 6:43 pm
Hi Bradford,
You requested that I…
Warring for your culture side is when you argue why your side is right.
Shield bashing is when you argue the other side is wrong by framing them as the aggressors.
Comment by Thought Provoker — February 16, 2008 @ 6:43 pm
February 16th, 2008 at 8:07 pm
Thanks for that clarification TP.
Comment by Bradford — February 16, 2008 @ 8:07 pm
February 16th, 2008 at 9:17 pm
Hi, Thought Provoker. You said
Yes, this is an intriguing position, since it would carry little force if Dawkins didn't realize full well that the overwhelming majority of theists don't accept the proposition that there are fairies dwelling at the bottom of gardens.
Earlier in this thread, you said
Would that mean you were teetering on the verge of acknowledging fairies at the bottom of gardens? (Didn't think so.)
And please rest assured that your willingness to consider "a universal consciousness" nicely supports any pre-existing reputation you might have as a seeker after the truth (to the extent that we are able to discern it).
Comment by Lutepisc — February 16, 2008 @ 9:17 pm
February 17th, 2008 at 2:22 am
Joy,
It seems to me that you have no idea what you're talking about.
Renormalization group (RG) is a mathematical formalism that constrains a physical theory near a scale-invariant fixed point. Its applicability to physics has been thoroughly tested in the realm of condensed-matter (CM) physics, where scale invariance arises naturally near critical points. Note that in CM we know the physics at the (high-energy) lattice scale and so we can test whether this physics is important to the (low-energy) behavior near a critical point. The answer is it isn't. Ising ferromagnets on the square, triangular, hexagonal and other lattices exhibit the same critical behavior, so RG is well regarded and completely noncontroversial.
Likewise, in particle physics it does not matter how divergences are regularized at high energies (something we don't know for sure). Renormalization-group mathematics tells us that it doesn't matter. One can formulate a perfectly sensible theory that deals just with the low-energy sector and one can test its predictions, which agree with experiments very well. Ponder the accuracy of QED. Are we completely satisfied with this situation? Not quite (hence string theory), but having good answers for our low-energy physics is much better than having no answers at all. Consciousness involvement at high energies is, as far as I understand, is pure speculation. There's not even anything approaching a theory in this direction.
And I don't think particle theorists have any grudge towards Aspect's results: relativistic QFT is fully compatible with the standard QM: as Dirac famously said, QFT is a marriage between QM and relativity. QM does have a problem with general relativity (GR) in the sense that GR is nonrenormalizable. But that has nothing to do with quantum nonlocality or Aspect's experiments. And consciousness isn't likely to solve that problem. String theory is a much more likely candidate for that, warts and all.
Comment by olegt — February 17, 2008 @ 2:22 am
February 17th, 2008 at 11:26 am
Hi Olegt,
I am glad you decided to join us.
You wrote to Joy…
What gave you the first clue? Was it when she said…
"Hahaha!!! Oh, heavens no! I struggle to wrap my head around stuff just like everybody else (it makes me cross-eyed!)."
While I am encouraged that you took the effort, I hope it isn't your intent to simply antagonise people with your superior knowledge.
I know it takes a lot of patience and requires ignoring the insults and assults to the ego, but you may find that a couple of people around here are actually interested in learning. Please, count me as one of those.
I take it that you don't consider Penrose's ideas (and those who agree with him) as "approaching a theory in this direction".
And what do you think of Penrose's Twister Theory?
I suggest the fact that "QM does have a problem with general relativity' means there is a problem. Is there any doubt about the reality of general relativity?
Penrose brings QM and GR together. In the other thread at AtBC you seem to indicate that Penrose's ideas concerning quantum gravity might be true but unnecessary because current QM models are good enough.
I argue current QM models aren't good enough if they have a problem with GR.
Thank you again for your participation. I look forward to your response.
Comment by Thought Provoker — February 17, 2008 @ 11:26 am
February 17th, 2008 at 11:46 am
olegt:
This is not my thread, so the behavior of this 'gator in his very first post to the forum can be preserved for posterity. I'll consider it a reminder of why we don't invite these creatures to cross our threshold.
To the rest of Swampy's display of hormonal overload:
a) Never said they did.
b) I know.
c) Sure it does.
d) It's called "Unitary Crisis."
I did not invent it. Strings can't cure it unless they somehow become scientific (and pass the tests).
Have fun, TP. You're the one who asked for it.
Comment by Joy — February 17, 2008 @ 11:46 am
February 17th, 2008 at 11:49 am
Hi Joy,
I know, I know.
This wouldn't be the first time I have had to struggle with getting what I asked for.
I thank you for your restraint.
P.S. I wouldn't mind a little help now and then though.
Comment by Thought Provoker — February 17, 2008 @ 11:49 am
February 17th, 2008 at 12:17 pm
Hi All,
A couple of pieces of information from Penrose's The Road to Reality.
pages 902 and 903
Penrose is noted for being one of the few physicists who challenge the string theory.
If I understand correctly, Penrose's answer focuses on more holistically unifying different aspects of reality. From Chapter 33 of Penrose's book (where he describes his Twister Theory)…
page 958.
Comment by Thought Provoker — February 17, 2008 @ 12:17 pm
February 17th, 2008 at 12:43 pm
Your first trip to the plate comes with that preface. It added nothing to the substance of your comment.
Comment by Bradford — February 17, 2008 @ 12:43 pm
February 17th, 2008 at 1:37 pm
Hi TP,
Twistor calculus is a set of mathematical tools, just like algebra or field theory. It can be useful in physics, but so far no one has built a theory of quantum gravity on its basis. The problem is not the lack of right mathematics, it's the lack of physical principles around which a theory could be built. (An example of that would be axioms of Einstein's special relativity: all inertial reference frames are equivalent, speed of light does not depend on the speed of the observer or source etc.)
The unsatisfactory situation wherein quantum mechanics and general relativity are incompatible with each other is not likely to be fixed in the near future. Not because we are lacking in intellectual power but simply because there are no experiments that would involve both quantum mechanics and gravity. We can't smash particles at Planck's energy and won't be able anytime soon. Experience shows that one can't build a physical theory from scratch, one needs lots of hints from experiments and with quantum gravity we're just out of luck.
If you are interested in quantum decoherence, forget quantum gravity and twistors. Understanding of this phenomenon will come from experiments conducted in the areas of atomic physics (supercold atoms) and condensed matter (electrons in quantum dots).
Comment by olegt — February 17, 2008 @ 1:37 pm
February 17th, 2008 at 6:14 pm
John
We do not know what caused the universe, so any theory of what caused the universe muyst necessarily be invoking an unknown. However, quantum fluctuations are know, so this is not as radically unknown as a supposed intelligent creator entity.
I am only suggesting this as a possibility, not as Truth. I think belieiving in a intelligent creator entity requires a leap of faith.
Opinion noted. When you have the slightest evidence for your intelligent creator entity let me known.
You might like to look at this web page, by the way:
http://www.colorado.edu/philos...
Bradford
What? There is a "lack of causal specificity" in the latter statement because of the way you made the statement; not because of any lack in science. IDists (creationists to be more accurate) say God did it, and leave it at that. Scientists say natural forces did it, then do the science to support the claim.
Comment by The Pixie — February 17, 2008 @ 6:14 pm
February 17th, 2008 at 6:18 pm
Hi Olegt,
Thank you for your reply. You wrote…
Some more from Penrose's The Road to Reality…
All these ideas concentrate on the construction of notions of 'spacetime' that take on aspects of discreteness or 'quantum' characteristics of some kind. In the remainder of this chapter I shall describe a quite different family of ideas, namely those of twister theory (to which I have, myself, now devoted over 40 years!) in which there is no discreteness specifically imposed upon spacetume. Instead, spacetime points are deposed from their primary role in physical theory.
…
Another guiding principle behind twistor theory is quantum non-locality. We recall from the strange EPR effects discussed in [sections 23.3-6], and more specifically from the role of 'quanglement'…
The twistor description of spacetime indeed turns out to be a non-local one; moreover, there is a fundamentally 'holistic' character to the twistor description of physical fields
…
We shall also begin to see how twistor theory finds a remarkable and unexpected deep relation to general relativity, and that it provides an intriguing perspective on QFT, particle physics, and the possible non-linear generalization of quantum mechanics.
How do these ideas indeed begin to come together in twistor theory? As a first step towards the understanding of twister ideas, we may think of a twistor as representing a light ray in ordinary (Minkowski) spacetime. One can regard such a light ray as providing the primitive 'causal link' between a pair of events (i.e. of spacetime points).pages 692 to 694
My version is that all quantum effects are interconnected via spacetime because the path lengths of light rays are ZERO.
I think Penrose is offering a fundamental insight into the reality of both large and small physics. A holistic, unified explanation of GR and QM.
One of the things I have mentioned to ID proponents is the propensity of complicating things more than they have to be. I consider this a form of confirmation bias and protection. For example, sometimes it seems like Bradford practically lives on the complexity of OOL research.
Excuse me for pointing out how you appear to be doing something similar. Your default QM answer is incomplete, but rather than explore a more understandable and complete answer, you are hanging your hat on a presumption that as long as you can't be proven wrong "anytime soon" we should follow the herd.
As you are aware, Penrose et al are proposing the FELIX experiment. Here is a link to Towards quantum superpositions of a mirror
And while I wouldn't be surprised if you felt the experiment would be insufficient to get you to separate from the pack, I am curious as to what you dislike about Penrose's theory.
Let me clue you in on something I probably mentioned before. I have two levels of interest. First, I am interested in understanding Penrose's theory, right or wrong.
So, therefore, I would welcome any suggestions on where I am misunderstanding Penrose.
I would also be interested in understanding how the Many World's interpretation makes sense, but no one seems to want to defend it past "it works as well as any other interpretation". To which I ask if the same is true of the GodDoesIt quantum interpretation?
The second level would be to understand the weakness of Penrose's logic.
I do not consider Penrose's deviation from "standard QM" to be a weakness.
Everyday computers and appliances using QM are just around the corner. My engineering instincts tell me that the PhD types are making this more complicated than it needs to be. The answer is staring us in the face.
What is the answer?
I think Penrose is on the right path, but many physicists are resisting it because of the uncomfortable implications. Especially in the area of bioquantum mechanics.
Comment by Thought Provoker — February 17, 2008 @ 6:18 pm
February 17th, 2008 at 8:23 pm
TP:
TP, I'd like to see Penrose enjoy success with his theory but it seems to me that olegt is pointing to some very real experimental problems not likely to be resolved any time soon. I wish I were in a better position to evaluate conflicting claims but I at least think I get the gist of olegt's point.
Comment by Bradford — February 17, 2008 @ 8:23 pm
February 17th, 2008 at 8:30 pm
God did it is no more scientific than natural forces did it. There is a lack of causal specificity in both statements. IDists share this much in common with Dawkins. Both sides believe scientific data can be used to support their respective beliefs.
I chose my words carefully. I did not mention a particular natural force or a specific mechanism. The phrase "natural forces," when not detailed, does lack causal specificity although it suffices as a philosophical belief.
That canard gets tiresome. You can do better.
Comment by Bradford — February 17, 2008 @ 8:30 pm
February 17th, 2008 at 9:25 pm
Bradford:
Perhaps oleg simply wishes to point out that his preferred alternative (strings, I presume he has a favorite among the many) is as untestable as OR, even though it multiplies the unknowns in a most non-occam-like way. Penrose has a single operator (so does Matti, but he's got more dimensions to transition through).
Fortunately for Penrose, the biophysical application – Orch-OR – is testable and some of that has been going on, not all of it proprietary. Each technical development or test sets the stage for more to test. It is much less difficult to construct designed analogues of molecular structures (or work with the molecular structures themselves) than it is to measure Planck level separations in spacetime or gravitons that collapse them.
It might boil down to a situation where "know thyself" will eventually allow us to know the universe. Seems fairly apropos to me.
Comment by Joy — February 17, 2008 @ 9:25 pm
February 17th, 2008 at 10:46 pm
Hi Bradford,
You wrote…
Of course you do.
Both you and Olegt are presuming that your respective fields of interest are so complicated that they won't be resolved any time soon.
Now, I happen to think in Olegt's case it might be a matter of job security assuming this is the Olegt who we are talking to. If I were him, I wouldn't be overly eager to embrace a radical departure from standard QM either.
Allow me to expand on Joy's comment.
Penrose is very much the mathematician. I can almost tell that black holes became real to him in 1965. He didn't need tangible evidence, he had all the evidence he needed in his mathematical models. It all made too much sense.
However, there were a lot of people refusing to accept it without verification. I understand that this type of mentality is the main reason neither Penrose nor Hawking have received a Nobel Prize.
It's not enough to be right.
Penrose knows that QM is non-algorithmic because he knows nature is inherently non-algorithmic. He sees it in Kurt Gödel's incompleteness theorms. Penrose figured out the ultimate solution to the non-periodic tiling puzzle which Penrose indicates can't be solved algorithmically.
Penrose started the Twister Theory in 1967. I can all but see his thought process. Like Black Holes, Penrose doesn't need tangible proof. To him, the twistor theory is real. He has worked it out. It makes sense except for one thing, the roll of consciousness. In 1989, he starts working on that and suggests, somehow, someway, consciousness is directly coupled with quantum mechanics.
Meanwhile, the real reality starts catching up. It looks like Black Holes are real. Penrose's Tilings shows up in nature as quasicrystals. A Dr. Hameroff suggests microtubules act like quantum computers inside neurons. Libet demonstrates hard-to-explain timing of consciousness (hard to explain if consciousness is just an unconnected classical Turing machine).
What is going to happen going forward?
We are getting better at keeping things in superposition. We are developing techniques to isolate and hold states of coherence. Even if Penrose's FELIX experiment doesn't directly test it, eventually coherent limits will be found. Penrose knows the limit is tied to Planck's constant of the form E ≈ h/t with E being self gravitational energy due to the superposition separation.
However, there will still be those who will reject it waiting for their favorite (but incomplete) explanation to be proven wrong in some high energy, high cost experiment.
And when biologists determine that life makes extensive and direct use of Quantum Mechanics in things like photosynthesis and DNA processes, there will still be people coming up with strained explanations for Libet's data.
So, as the old song says, the beat goes on.
"¦and so will the dueling metaphysics.
Someday, people will pick up Penrose's The Road to Reality and wonder how this guy made such lucky guesses. Either that, or wonder why so few people listened to him.
Comment by Thought Provoker — February 17, 2008 @ 10:46 pm
February 18th, 2008 at 5:00 am
Bradford
It sounds like you chose your words carefully to give the impression science is as vacuous as creationism, when the reality is that science has a vast body of knowledge behind the phrase "natural forces did it" and creationism has zero behind "God did it"
Labelling it a "canard" does not make it so. And it was you who said there is a lack of causal specificity in the "God did it" statement. Objecting to an argument because it is tiresome really is not convincing.
TP
I would have thought that a radical departure (assuming it is a better model) would be welcomed as an oppurtunity for a scientist to make a name for himself.
Comment by The Pixie — February 18, 2008 @ 5:00 am
February 18th, 2008 at 8:05 am
Science has limits. Everyone is aware of benefits that have resulted from scientific progress. The science backed up by a great deal of knowledge is science that shows us how chemicals react and why. The vacuousness of scientism is indicated by those who take organic chemistry well beyond where knowledge is supportive and attempt to make it indicate something about how life came to be without the evidence to back it up.
The canard lies in your claim that IDists say God did it and leave it at that. This is clearly a lie. Is that what Mike said in The Design Matrix? Which TTer says God did it and there is nothing more to discuss?
Comment by Bradford — February 18, 2008 @ 8:05 am
February 18th, 2008 at 11:40 am
Hello, TP.
Once again, twistors are, first and foremost, a mathematical tool. The simplest, though imprecise analogy would be vectors. Vectors are convenient mathematical objects that are extremely handy in classical mechanics and electromagnetism. Vector algebra greatly simplifies the mathematical notation and incorporates the rotational symmetry of our 3-dimensional world into a physical theory (or 4-dimensional Minkowski space in special relativity). However, vector algebra on its own does not equate with a physical theory. One must observe the dynamics of physical objects to infer Newton's 2nd law, F = ma.
Likewise, the mathematics of twistors provides some interesting clues about the structure of a physical theory. Unfortunately, the idea is based solely on math and that is usually not enough to guess the entire physical theory. Twistors aren't real objects. Just like integers, vectors and geometrical shapes, they're mathematical abstractions. Black holes, on the other hands, are real: they can be and have been observed, albeit indirectly (see Sagitarius-A*).
String theory suffers from the same problem: it's a mathematical framework, not a physical theory, akin to the quantum field theory (QFT). The QFT is the mathematics of point-like objects (particles) in a Euclidean or Minkwoski space. It is applicable to a variety of physical systems: quantum electrodynamics (electrons plus photons), quantum chromodynamics (quarks plus gluons), ferromagnets near a critical point (spins) and even finance (derivative pricing). But QFT on its own does not describe any physical system. Same with string theory.
Since both twistors and strings are mathematical tools, one shouldn't think that they are at odds with each other. Proof to the contrary is a recent (2003) work of Ed Witten in which he used twistor math to solve certain problems in string theory. Here's Penrose's take on it: Strings with a twist.
Lastly, I find the conspiracy theory about my preference for the Copenhagen interpretation mildly amusing. As I said elsewhere, for all practical purposes all of the current interpretations of QM give the same results, and that is applicable to my work. When I calculate expectation values of certain quantum observables, it does not matter which interpretation of QM I use. I can announce that I am a hard-core Penrosian today at lunch and none of my colleagues will care. So don't worry, my job is secure regardless of where I stand with respect to Penrose.
Comment by olegt — February 18, 2008 @ 11:40 am
February 18th, 2008 at 12:11 pm
Bradford
Then please do not claim that science is lacking causal specificity with the statement "natural forces did it".
Abiogenesis is an active research area, with real scientists doing real science. I would agree that at best they will only find out how it could have happened, but that is a lot more science than IDists are doing at the moment.
First off, if we are talking about ID, we really mean "the designer did it". I am only half way through the Design Matrix; I have not found anything there to suggest what further research will be done once design has been confirmed. What areas do you think will become opened to science? Are IDists going to investigate the nature and purpose of the designer?
Many people claim ID is already science (Mike of course is not one of them), and many are convinced there is already enough evidence of design. I wonder what new science they are doing.
Comment by The Pixie — February 18, 2008 @ 12:11 pm
February 18th, 2008 at 12:24 pm
Why distort what I actually said? What I said was not that science is lacking causal specificity but rather "God did it is no more scientific than natural forces did it. There is a lack of causal specificity in both statements." Once you attach a specific valid biochemical pathway in place of natural forces you have a scientific statement. Until you do something similar you have naturalism. There is a difference between science and a philosophy. Are you aware of that?
Comment by Bradford — February 18, 2008 @ 12:24 pm
February 18th, 2008 at 12:37 pm
Hey Pixie:
I have an honest question. Can science come to the conclusion that Abiogensis is beyond the power of natural forces or is this conclusion impossible for science to make?
I'm not saying that we are at that point but suppose in a thousand years we still haven't been able to indentify a sufficiently plausible path way. What then?
Peace
Comment by fifth monarchy man — February 18, 2008 @ 12:37 pm
February 18th, 2008 at 1:28 pm
Hi oleg,
Thank you for responding. You wrote…
Please excuse my provocation. I was hoping you would react the way you did. I think it helps to clear out potential obstacles for an open discussion.
For my part, I am earnestly interested in looking for holes in my understanding of Penrose's ideas and/or holes in Penrose's logic.
For example, you have mentioned twice now that "…twistors are, first and foremost, a mathematical tool." I am not disagreeing with this statement. However, I think Penrose's translation of mathematical models into reality is a little stronger than what you are implying. I suggest Penrose felt Black Holes were real long before any tangible evidence was found. I could easily be wrong on my understanding of Penrose but in the 1994 debate Stephen Hawking seemed to be critising Penrose's fixation on worrying about what is real or not.
I suggest you are doing something similar by implying that any mathematical model is just as good as another as long as it matches specific observations in specific fields of study.
I could be convinced that Penrose is wrong but, frankly, his holistic approach makes a lot of sense to me. Even if it causes him to have to make way-out hypotheses about the role of consciousness to make the model complete. Reality has to be real for all situations, not just QM or GR or the macro FAPP world.
That being said, I THANK YOU VERY MUCH for providing the Penrose link….
"The geometrical correspondence between twistor space and the four-real-dimensional space-time of special relativity means that twistor space now does double duty: it simultaneously supplies the needs of both the Calabi-Yau spaces and space-time itself. Accordingly, the strings now become complex curves — Riemann surfaces, to be specific — in twistor space!
The development of these ideas is due mostly to Edward Witten of the Institute for Advanced Study in Princeton, New Jersey, who has been the main driving force behind new directions in string theory since the late 1980s. It seems to me that there are some striking developments coming from this new approach, and it will be exciting to see how far these ideas can be extended towards a comprehensive physical theory with something serious to say about quantum gravity.
Twistor theory has been around for a little over four decades now. Like string theory, it has had more impact on pure mathematics than on clear-cut physical results, but as the string theorists begin to take it up it may just be coming into its own as a physical theory. And, since fully fledged twistor theory calls for just three space dimensions and one time dimension, the first result of this emerging union may well be that those extra dimensions of string theory slip quietly away." link
So now that you provided Penrose's positive argument, why aren't you a "hard-core Penrosian" What is wrong with Penrose's logic?
A lack of experimental evidence is one thing. But why treat a model with clear holes as being equivalent to a model that doesn't have holes?
Even Joy was voiced reservations about the leap of faith in Penrose's quantum gravity but, if I understand correctly, there isn't anything absolutely preventing it from being correct.
Comment by Thought Provoker — February 18, 2008 @ 1:28 pm
February 18th, 2008 at 1:42 pm
TP wrote:
The problem that I have with the people that preach NOMA such a S. J. Gould (and you) is that they are among the first ones to violate it. Gould's book, Wonderful Life, is a prime example of this. I don't see how anyone, with philosophy 101 background, can conclude that Gould isn't involved in a lot of philosophical (metaphysical) speculation, if not pontification, in this book. Isn't the argument that the evolution of life is non teleological a metaphysical one? Isn't that the claim Gould is making in his book? Doesn't that violate NOMA?
Bradford is the sponsor of this thread. He didn't stipulate any where that anyone had to adhere to any kind of NOMA standard. Did he ask you to start policing this thread? Does the topic really lend itself to any kind of adherence to NOMA? IMO it doesn't.
Is NOMA now the official standard of Telic Thoughts? If it is, when did that happen? What is the definition of Telic? Doesn't it have something to do with teleology? (It does.) How could you empirically prove something is or isn't teleological?
I've tried my best to play by the rules and keep the thread on subject. Why are you trying to derail it? If the topic is not your "cup of tea" why don't try another topic or go someplace else? To me that seems to be the ethical thing to do.
Anyone who has participated in a discussion with you over the past year knows what you think about NOMA. We have all heard over and over again and again. It's one thing to present it as a topic for discussion it's another to continually preach and pontificate about it. I don't know about anyone else but I for one am getting a little tired of this neo authoritarian NOMA nonsense. Please realize other people, besides you, are perfectly capable of thinking for themselves.
Did you read Athony Flew's latest book (see below for title). He quoted Socrates who was willing to follow the evidence wherever it leads. I believe in an eternally existing transcendent intelligence because at the present it is the best explanation of the evidence(comparing all points of view) as we presently know it. I am certainly willing to change my POV if new evidence requires it. You can't IMO get much more open minded than that.
(Sorry if this comment has been some what blunt. I tried my best to restrain any unnecessary negative feelings and to be as polite as possible. I sincerely hope it has come across that way.)
Pixie wrote:
A t the beginning of our discussion I wrote;
We certainly know that intelligence exists. We (you, me, other humans) are, afterall, are intelligent. Didn't you say this? So, intelligence as a causal agent is something we know at least something about.
I would strongly disagree that there isn't any evidence supporting my position. Former atheist Anthony Flew would certainly agree. That is the argument that he makes in his latest book, There Is a God: How the Worlds Most Notorious Atheist Changed his Mind. Have you read it?
Comment by JOHN_A_DESIGNER — February 18, 2008 @ 1:42 pm
February 18th, 2008 at 2:05 pm
Evidence for a creator? DNA. Oh, I know. It resulted from unidentified chemical pathways. Keep the faith.:wink:
Comment by Bradford — February 18, 2008 @ 2:05 pm
February 18th, 2008 at 2:15 pm
TP,
There is a big difference between twistors and black holes. The former are abstract mathematical entities (like integers and vectors), the latter are physical objects (like atoms and superfluids). Physical objects can be observed and experimented with, mathematical ones only exist in our minds. Penrose believed in reality of black holes long before they were observed, which is fine with me. However, reality of twistors (or integer numbers) is an oxymoron. I'm only half joking.
That illustrates the gulf between physics (a natural science) and mathematics (not). To be valid, a mathematical construction only needs to be internally consistent. Penrose's twistor mathematics is perfectly valid and useful. Whether his idea about gravity causing quantum decoherence is a correct physical theory remains to be seen. The universal nature of his theory does not make it correct.
In fact, this is the reason I am suspicious about it: there are no working theories of everything in physics. There are good reasons to believe that the physics of quantum decoherence will be resolved without any help from gravity. If the resulting theory won't reconcile quantum mechanics with gravity, so what? That may well be a separate question.
Comment by olegt — February 18, 2008 @ 2:15 pm
February 18th, 2008 at 2:24 pm
Hi John,
You wrote…
I opened my previous comment with…
"I'll apologize up front for beating my OMA/NOMA drum again…"
And I agree that this is as off topic as discussing Gould's or Flew's philosophical opinions.
Oleg, Joy and I are discussing the scientific subjects Bradford brought up in the opening post. We are discussing various theories like String Theory, Twistor Theory and Orch OR theory of consciousness.
Would you care to join us?
Comment by Thought Provoker — February 18, 2008 @ 2:24 pm
February 18th, 2008 at 2:47 pm
TP
Keep in mind that after our recent discussion you can no longer discuss Orch Or and still hold to NOMA Because if the moral law is real then Christianity is part of that theory.
I could not resist
carry on
Peace
Comment by fifth monarchy man — February 18, 2008 @ 2:47 pm
February 18th, 2008 at 6:21 pm
John
Yes I did. Let us move on.
Oh yes.
Where we part company is your claim that this intelligence or consciousness is a fundamental aspect of the universe. You do not seem to be address that at all now.
I have not. What is that evidence that he discusses?
Bradford
DNA cound have resulted from unidentified chemical pathways (unless you can prove otherwise). We do not know. Therefore we have no evidence for the creator there. Only faith.
Comment by The Pixie — February 18, 2008 @ 6:21 pm
February 18th, 2008 at 6:45 pm
Bradford:
That is just so pathetic. DNA as evidence for a creator. Is that the best you can do?
Comment by Raevmo — February 18, 2008 @ 6:45 pm
February 18th, 2008 at 7:07 pm
Hi Oleg,
You wrote…
…and…
I thank you for your patience. I'm apparently not communicating my concept very well. Let's try the more basic version I was attempting back at AtBC.
One way to view the universe is that it is three dimensional Euclidean Geometry where everything follows the mathematics of Newtonian Physics. Time being thought of as causing the complete 3D space to progress snapshot by snapshot, like a frames in a motion picture.
The mathematics of this view can vary, without changing the basic view. A trivial example would be to use polar (r, Φ, θ) coordinates instead of Cartesean (X, Y and Z) coordinates. I get the impression you are trying to suggest that Penrose's Twistors are only a different way of looking at the same thing.
I'm suggestion there is more. There is an "AH HA" behind Penrose's math. It is the concept, not the mathematical construction that Penrose is trying to communicate.
Schwarzschild used polar coordinates in his attempt to explain curved space. Clearly Schwarzschild was doing more than performing a coordinate conversion (Cartesean to Polar) of Minkowskian Geometry. The "AH HA" is that space actually curves.
Was Schwarzschild's concept just a "mathematical construction"
Part of the argument I was having with the denizens of AtBC was their insistence that spacetime relativity MUST involve acceleration. I was trying to explain the "AH HA" that it actually involves differing path lengths in four dimensional spacetime.
The equations for "special" relativity work under specific, limited circumstances. To me, that means that they are less representative of reality than the equations that combine both special and general relativity.
Those equations demonstrate to me that varying path lengths through 4D spacetime are really real.
To me, Penrose's Twistor Theory is demonstrating the "AH HA" that the path length of light rays are, in fact, ZERO!
And this reality explains the non-locality effects of Quantum Mechanics.
My questions…
1. Do you think I am misunderstanding what Penrose is suggesting?
2. If I am understanding it correctly, do you think Penrose's Twistor THEORY (not just the math) is flat-out wrong?
Comment by Thought Provoker — February 18, 2008 @ 7:07 pm
February 18th, 2008 at 8:34 pm
Hi Fifth Monarchy Man,
The little word "if" makes a big difference. That, and you have yet to provide your logic chain explaining how you arrived at your conclusion.
The thread is still available for continuing our discussion. Here is the link to my last entry.
Alternatively, you could provide a quick summary of your logic in a rabbit thread like this one.
Comment by Thought Provoker — February 18, 2008 @ 8:34 pm
February 18th, 2008 at 9:19 pm
Hmm. Let's see. A polymer, whose biological function is sequence dependent but not its chemical nature, arises from a non-cellular world based on random chemical reactions.:roll: Or based on purposeful intent. The latter is consistent with our experience. This is anethema to you for one reason- nature is presumed to be without purpose. Might as well define it that way. But that view is touchy feely at its core- not based on rational thought.
Comment by Bradford — February 18, 2008 @ 9:19 pm
February 18th, 2008 at 9:43 pm
TP,
Penrose pointed out that 4-vectors with null norm can be expressed very simply in terms of twistors, but he did not prove that light travels along null geodesic and he did not need to: that has been known since Einstein. This tells me that most likely you do not understand Penrose.
And no, I don't consider Penrose's physical model to be "flat-out wrong". Lack of experimental tests and an unfinished nature of his theory means that its success or failure is too early to judge.
Comment by olegt — February 18, 2008 @ 9:43 pm
February 18th, 2008 at 10:42 pm
Hi oleg,
Thank you for your response. You wrote…
I was not suggesting Penrose was proving the concept of the "null geodesic" any more than I would suggest he was proving the concept of time dilation or the curving of space. I was offering that Penrose is attempting to do something similar to what Minkowski and Schwarzschild did back in the very early 1900's.
BTW, you didn't answer my question. Would you call the geometries posed by Minkowski and Schwarzschild "abstract mathematical entities" and/or simple "mathematical construction"?
Meanwhile, I thank you again for the link to the Penrose paper. It is a lot easier to copy and paste than it is to type sections from a 1000 page book. Here is more on Penrose's ideas"¦
"The twistor viewpoint is to regard light rays as more primitive than points in space-time, so it takes "light-ray space" — the space whose individual "points" represent entire light rays in space-time — to be more fundamental than space-time itself. This turns out to have wide-reaching consequences.
In the normal view of space-time, two points can sometimes be linked by a light ray, which is usually represented as a line passing through the space-time. But in twistor theory, a light ray is defined as a single point in light-ray space, and a space-time point P is represented by the celestial sphere's worth of light rays through P — in other words by a complex curve (a Riemann sphere) running through light-ray space. link
I can easily accept that I could be misunderstanding what Penrose says, but when I read things like "more fundamental than space-time itself" it seems that Penrose isn't treating this as some abstract mathematical entity. And I am having trouble understanding the difference between the concept of light ray path lengths being zero and, in Penrose's words, "…a light ray is defined as a single point…".
Let me ask you a direct question.
In the Twins Paradox, do you think the traveling twin is actually taking a shorter path through 4D space-time, or is that just a mathematical construct to you?
Comment by Thought Provoker — February 18, 2008 @ 10:42 pm
February 18th, 2008 at 10:55 pm
Hi All,
I would like to point out that from my investigations of Quantum Mechanics I find a lot of physicists appear to think along the lines Oleg is demonstrating.
Whatever works.
This is the exact opposite of the kind of dogmatic materialism that some ID Movement leaders have described.
Comment by Thought Provoker — February 18, 2008 @ 10:55 pm
February 18th, 2008 at 11:59 pm
TP,
I just want to make sure you understand that null geodesic came first and twistors later. Glad we agree on that. Briefly on the rest of your questions.
Schwarzschild himself viewed his exact solution of Einstein's equations as a neat mathematical trick that allowed to verify Einstein's approximate solution in the limit of a weak gravitational field. According to his scientific biography posted at the University of St. Andrews, "Schwarzschild himself makes clear that he believes that the theoretical solution is physically meaningless, so making it very clear that he did not believe in the physical reality of black holes." While I agree with you that it's great to know exactly the properties of spacetime around a spherically symmetric mass, I see no reason to worship the Schwarzschild metric. It is a mathematical construction, just like the exact solution of the Schroedinger equation for hydrogen is a mathematical construction. A very useful one, to be sure.
Minkowski's spacetime has become so ingrained in theoretical physics that I am tempted to agree with you and say that it's more than just math. While in special relativity it chiefly makes calculations more transparent, doing general relativity would be impossible without the notion of a curved 4-dimensional spacetime.
Whether Penrose's twistors will provide a similar impact remains to be seen. As I mentioned, Witten had found them useful in a particular context, but we don't teach them in GR classes just yet. Time will tell.
It would take me an inordinate amount of time to do justice to the twin paradox. Instead, I'll point you to the Wikipedia article, which gives a decent introduction. To quote,
Of course, the symmetry is broken because one of the twins had to accelerate when he turned around. That is the resolution of the paradox and people at AtBC were right to point out the importance of acceleration. If an object accelerates its worldline in Minkowski space is curved and vice versa. Thus a shorter interval (proper time) of the traveling twin and the fact that he accelerated are inseparable. To quote the article again,
Hope this helps.
Comment by olegt — February 18, 2008 @ 11:59 pm
February 19th, 2008 at 8:25 am
The word "accelerate" can throw people sometimes, and they think they have to account for General Relativistic effects. Just assume the twin magically turns around. When we measure motion, we have to measure it in relation to something else. Simply, in Special Relativity the distance from the Earth to the destination star appears shorter to the one who is traveling on both the outgoing and incoming trips. At high enough velocities, it's just a single footstep each way.
Comment by Zachriel — February 19, 2008 @ 8:25 am
February 19th, 2008 at 9:23 am
Hi Zachriel,
While I agree that this is the quickest way to get to the right answer, ignoring the turnaround is precisely what leads to the paradox. If you split the trip into three parts (Twin B is going away, turning around and coming back), everything looks symmetric in Parts I and III: the twins are receding from or approaching each other at the same speed and their reference frames are inertial. It's Part II, in which Twin B accelerates to turn around, that is responsible for bending his worldline in Minkowski space and making its length shorter.
GR enters the story because you need to calculate the length of a curved path. Strictly speaking, that requires differential geometry, which is precisely the kinematic side of GR. Fortunately, Twin B's path is dominated by Parts I and III, which are straight lines, so that the curved section does not contribute much to the overall length (assuming he was not moving too fast, in which case Parts I and III may turn out to be short).
Comment by olegt — February 19, 2008 @ 9:23 am
February 19th, 2008 at 11:44 am
I'm not sure it's such a paradox.
{edited}
Of course, at those sorts of velocities, it would take the energy of a millions stars to power the magic ring, the mass of the travelor would crush his twin, while the remnants of the Earth, Sun and much of the galactic sector would be dragged along for the ride.
Comment by Zachriel — February 19, 2008 @ 11:44 am
February 19th, 2008 at 1:03 pm
Pixie, here is a response to on of your questions. I will try to address the other one later.
I think Flew makes the best argument in chapter 7 which is entitled, "How Did Life Go Live?" He begins to make what I consider the key to his argument by quoting Paul Davies who wrote: "life is more than just complex chemical reactions. The cell is also an information storing and processing and replicating system. We need to explain the origin of this information and the way the information processing equipment came to exist."
Flew then comments: [Davies] "emphasizes the fact that a gene is nothing but a set of coded instructions with a precise recipe for manufacturing proteins. Most important these genetic instructions are not the kind of information that you find in thermodynamics and statistical mechanics; rather, they constitute semantic information. In other words they have a specific meaning. These instructions can be effective only in the molecular environment capable interpreting the meaning in the genetic code."
He concludes with another quote by Davies:
"The problem of how meaningful or semantic information can emerge spontaneously from a collection of mindless molecules subject to blind and purposeless forces presents a deep conceptual challenge." (Both Davies quotes are from "The Origins of Life II: How Did It Begin?")
I should make it clear; at least as I understand his position, Paul Davies believes that science will eventually be able to give us a natural explanation for the origin of life. Nevertheless, he is very honest about the problems and challenges that OOL researchers face. The bottom line, however, is that at present time nobody has a clue how life got started naturalistically, nor can they say even if it did in fact started naturalistically.
My problem with such beliefs is that they are just beliefs. The fact that Paul Davies is a scientist doesn't make them any more credible than any other kind of beliefs. IOW beliefs are not scientific evidence.
How then is the genetic code evidence for an intelligent origin? It is because we know of other kinds of codes that are very similar: human language, computer programs, for example, that are created and manipulated by intelligence"”human intelligence. It's not only logical, but common sense to consider intelligence as the cause of an equally (if not more) sophisticated code, the genetic code.
Comment by JOHN_A_DESIGNER — February 19, 2008 @ 1:03 pm
February 19th, 2008 at 1:53 pm
Hi Oleg,
Thank You for your response. However, I expected you to go one way or the other. When you said…
…but followed up with…
That makes little sense to me because I can derive Schwarzschild Geometry from Minkowski's Geometry.
Starting with standard Minkowskian geometry"¦
ds^2 = dt^2 – dx^2 – dy^2 – dz^2
Converting Cartesian to polar (dx to r*dθ and dy to r*sinθ*dΦ and dz to dr)
ds^2 = dt^2 – (r*dθ)^2 – (r*sinθ*dΦ)^2 – dr^2
Allowing for curved space (simple 3D geometry)…
ds^2 = Gtt*dt^2 – (r*dθ)^2 – (r*sinθ*dΦ)^2 – dr^2/Gtt
The "magic" comes in deciding what Gtt is. If Gtt = 1, then it is flat, Minkowski. If Gtt is defined as "1 – Rs / r" where Rs is the Schwarzschild radius then it describes observable reality.
For example, if the Earth was crushed into a Black Hole, its Schwarzschild radius would be 8.87 millimeters. Based on this, we should be able to calculate the time dilation of the different clocks in the GPS satellite situation as follows…
radius of geosynchronous orbit is 2.656175×10^7 meters
radius of earth is 6.3781363×10^6 meters
Gtt for geosynchronous orbit is (1-0.00887/2.656175×10^7) = 0.99999999966606115937391173397837
Gtt for earth bound objects is (1-0.00887/6.3781363×10^6) = 0.99999999860931162603094574821175
Including the velocity of the GPS Satellite at 0.0000129217 times the speed of light and velocity of the earth bound clock of 0.0000017737252 times the speed of light results in a GPS to Earth clock ratio of 1.000000000447 with the Earth Clock running slower. This calculation corresponds to observations and explains how and why the GPS clocks are calibrated as they are.
Note that special relativity would suggest that the Earth clock should be running FASTER not slower (the homebound twin grows older quicker). Which brings us to the Twins Paradox and special relativity.
I see Zachriel has decided to join us, good. In the past, Zachriel and I have discussed the paradox associated with determining frames of reference. Why does one frame of reference get preferential treatment if everything is truly relative.
Time to bring out the Dilithium crystal clicking captain again. This time the captain is on a space station that is in geosynchronous orbit around Earth. But that is not how our erstwhile captain sees it. I sees himself as being stationary and experiencing no force (he is weightless). The Earth is stationary below him. He orders poor Ensign Keiths to take a 24 hour trip around the Earth. Keiths jumps into a shuttle and instantly accelerates to 0.0000129217 times the speed of light goes around the Earth and then instantly deaccelerates back to stop and then redocks to the space station. The Captain and Keiths compare watches. But it turns out that it is the Captain and not Keiths who experienced the time effects expected of the traveling twin.
How can this be?!?
I can explain to the Captain that four dimension spacetime is real and that he is traveling through it even if he thinks he is at rest. The reason the captain doesn't feel any forces is because he is traveling straight, it is space that is curved. While Ensign Keiths might have looked like he was moving quicky in the space-like dimensions, he was not. He was only moving in the time-like dimension (with slight movement in the space-like dimensions). Keith's acceleration and discontinuous movements have nothing to do with calculating the path length of Keith's travel.
I will follow up with actual numbers as needed (need to get back to work).
Meanwhile, I would be interested in what you and Zachriel have to say to our erstwhile captain other than it is too complicated to explain.
Comment by Thought Provoker — February 19, 2008 @ 1:53 pm
February 19th, 2008 at 3:03 pm
Hi All,
In case you are interested in how all this Twin Paradox stuff plays into the thread's topic, let me offer my version.
I am suggesting that paths through the four dimensional spacetime are really real and the geometry is such that some paths between two locations in spacetime are shorter than others. This leads to the realization that spacetime geometry is actually twisted inside out from our normal perception. All "light rays" have a path length of ZERO. "Light rays" are points, not rays.
From this it is easy to see how quantum effects are interconnected even if we perceive them as separated in space and time.
If consciousness is tied to a universal consciousness instead being only an emergent property of organic processors, then quantum effects provide a ready mechanism.
This is why I suggest this subject is relevant to a thread about new physics and new approaches to understanding the mind.
By the way, a fall out of Penrose's view of the universe is the concept that there is a whole lot more information stored in the universe than normally suggested.
Here is a link to the Princeton web site where there are videos of three hour long lectures by Penrose (starting October 17th, 2003)
The lectures are titled Fashion, Faith and Fantasy in the New Physics of the Universe "Fashion" is about String Theory (so I have been told). "Faith" is about questioning standard QM. I don't know about the third.
Here is the link to the middle one, Faith. I am not sure I am recommending it because I think the main reason I understand it is because I have read Penrose's books. Penrose goes through his presentation quite quickly and not always smoothly. It is an hour long. But if you are brave (or fool hearty) be my guest.
Comment by Thought Provoker — February 19, 2008 @ 3:03 pm
February 19th, 2008 at 5:15 pm
TP,
I have a feeling that we're going in circles and I don't have much time for that.
No, Schwarzschild metric isn't "derived" from Minkowski's. Rather, it is a solution of Einstein's equations for empty space in the spherically symmetric case. "Inspired" would be a better word.
There's no paradox in your example with Captain and Keiths. Captain was moving along a spiral in spacetime, whereas Keiths took the "straight" path along the time direction. Since the spiral path has a nonzero spatial component, its invariant length (proper time) is shorter. Yes, the Captain was moving along a geodesic and you might say that geodesics are longest paths, but that would only be correct in the infinitesimal sense: any infinitesimally small deviation from Captain's geodesic worldline will reduce its length, so it's a local maximum. However, it's not guaranteed to be a global maximum, so don't be surprised that Keiths' worldline, which differs substantially from Captain's (0 revolutions in space instead of 1), turns out to be longer.
No problem with that.
Interconnected by what? Invisible light rays?
And how are we supposed to test this theory?
Comment by olegt — February 19, 2008 @ 5:15 pm
February 19th, 2008 at 7:06 pm
Hi Oleg,
To my basic premise on the reality of spacetime geometry and "light rays" having zero path length (i.e. coexisting "points") you wrote…
I am sorry that you feel we are going in circles, because I'm seeing progress. Your lack of criticism of my analysis of the GPS situation suggests I got it right (at least no glaring errors).
The reality of curved spacetime and the lack of separation along the null geodesic may be trivial to you, but some of us are still struggling with it. It's nice to get confirmation.
Yes, there is no paradox if you accept the reality of the existence of a global spacetime frame of reference. The Captain is spiraling through the four dimensional geometry that makes up the reality of our universe (whether the geometry is named after Minkowski or Schwarzschild doesn't matter).
Oleg, I suspect that you wouldn't have any problems with concept presented in this paper. Why did Einstein Come Back to the Ether?
"In (1905) Einstein constructed a relativity theory that was based on the assertion that the ether was superfluous. In 1908 Minkowski formulated the theory of the "absolute world". The nineteenth century ether no longer existed. A new kind of ether (space-time) came into being. One could keep on maintaining the ether, and at the same time strip it of the notion of absolute rest. Einstein seemed to agree, and after 1916 he returned to the ether."
It will be interesting to see Zachriel's reaction. You see, I am under the impression that the "paradox" of the Twin's Paradox was caused by a presumption that there was no preferential frame of reference. I agree that without that presumption, there is no paradox.
So I am feeling you and I mostly agree on the GR side of things. It is when we flip over Null Geodesic (aka "Light Rays", aka "Twistor", aka spacetime points) into the QM side of things that we start to clash.
Let's start with a simple example of quantum experiments with VISIBLE light.
Here is a description of A Delayed Choice Quantum Eraser
Which goes into descriptions of how "photons" appear to be interconnected even though separated in space and time. If spacetime geometry is really real, then it is real for QM experiments too.
The spacetime separation of photons is ZERO!
There is no mystery because the photons aren't separated.
Penrose calls this no separation concept quantum entanglement or "quanglement."
I will get into how we test the Penrose/Hameroff's Orch OR later. For now, I want to build the foundation of the implications of Penrose's Twistor Theory or understand the flaw in Penrose's logic.
Comment by Thought Provoker — February 19, 2008 @ 7:06 pm
February 19th, 2008 at 7:27 pm
Of course. The Captain, being in geosynchronous orbit, was being accelerated. He would be aware of this as he would drift away from the Earth until pressed against the far wall. He *is* the traveling twin.
Comment by Zachriel — February 19, 2008 @ 7:27 pm
February 19th, 2008 at 8:01 pm
Every time I think I'm keeping up… I'm knocked back down to the reality that I've no idea what's being discussed.
Thanks to Olget, for his patience and participation (love the give-n-take (mostly) civil discussions on TT). Hope you decide to stick around and contribute in other blogs/discussions.
Thanks to TP for that Princeton lectures link… lots of good stuff there!
Okay, back to lurking.
Comment by Rob R. — February 19, 2008 @ 8:01 pm
February 19th, 2008 at 9:10 pm
Hi Zachriel,
Sorry Zach but I think you messed that one up. The Captain is just as much in geosynchronous orbit as his space station. Think of the Captain outside in a space suit. Too slow, he falls to Earth. Too fast, he drifts out into space. Just right, he stays in geosynchronous orbit.
Before you get too wrapped up in the gravitational situation let me offer another reference frame puzzler. This one has both twins out and about in space ships capable of relativistic speeds. After getting quite separated, the twins come straight at each other. One radios the other and says "look out your port window, there is a beautiful pulsar that is beating at precisely once a second. The other twin radios back, you need to calibrate your clock when we get back. It is beating once every second and a half.
I came up with this when I was trying to think of a way to determine if one is traveling in both time and space dimensions of the Minkowskian geometry that is our universe.
We could move perpendicular to known time sources like pulsars. If our clock appears to be running faster (the pulsar appears to be beating slower) then we are getting closer to traveling perfectly in the time direction and not in space-like dimensions.
This way we could play a game of hot/cold with different pulsars to hone in on traveling straight down the time axis of our universe.
Comment by Thought Provoker — February 19, 2008 @ 9:10 pm
February 19th, 2008 at 9:25 pm
Hi Rob,
Thank you for commenting. It is nice to know someone is listening.
I'm glad you liked the Princeton lectures. I might try to get to Penrose's third lecture tonight.
Comment by Thought Provoker — February 19, 2008 @ 9:25 pm
February 19th, 2008 at 9:36 pm
TP,
I didn't check your GPS analysis (no time for that).
The terms reference frame and spacetime have very specific meanings in physics and they are not the same. Spacetime is a four-dimensional continuum. Choosing a reference frame in spacetime amounts to creating a coordinate system. Coordinates can be chosen in infinitely many ways; likewise, there are an infinitude of reference frames.
Granek's essay mentions some interesting trivia but it has nothing with which a physicist could agree or disagree. OK, Einstein likened spacetime to the aether because it acts upon and can be perturbed by matter. The analogy did not take root: as far as I know, today no physicist calls spacetime aether. (Frank Wilczek uses the word to describe the condensate of Higgs bosons permeating the Universe, but that's not commonly accepted, either.) It's not a matter of testable science, it's semantics.
I don't think we agree here. One of the axioms of special relativity states that all inertial reference frames are presumed equivalent. The twin paradox is resolved when one observes that one of the twins accelerated during the turnaround, which means that his reference frame was not inertial and thus could not be used in the framework of special relativity. General relativity goes even further, allowing one to work in any reference frame, inertial or not.
You're playing loose with physical terms. Light rays aren't null geodesics, they travel along null geodesics. Null geodesics and twistors are two different mathematical objects.
No. While the Minkowski distance between a photon and its source (or any point on the light ray) is always zero, the interval between two photons emitted from the same point is not zero, unless they are emitted in the same direction and simultaneously.
Comment by olegt — February 19, 2008 @ 9:36 pm
February 19th, 2008 at 9:56 pm
TP,
This is completely wrong: there is no fixed time axis in our Universe as far as we know. Pulsars won't help, either. Suppose you measure period T when you are stationary with respect to a pulsar. If you start moving away from it, the pulsar will be red-shifted, which means that its frequency will go down and its period will be longer than T. The faster you are moving away from it, the longer its period will appear. There is no frame in which the period will be longest, there is always room for improvement.
It doesn't help that the Universe is expanding so that distant objects are moving away from us with a velocity increasing with the distance. If you choose a frame stationary relative to a pulsar at one location in the Universe, you won't be stationary with respect to other parts.
Comment by olegt — February 19, 2008 @ 9:56 pm
February 19th, 2008 at 10:59 pm
The spaceship would experience tidal forces, as would the Captain. There is more gravity on the near surface than the far surface. That means he and the ship are being stretched and compressed towards the planet's center of gravity. Assuming the Captain is standing perpendicular in Earth orbit, his feet would experience more gravity than his head, have a shorter orbit, and be pinched like wearing a pair of poorly fitted shoes. The Captain would also tend to drift (though perhaps not to the outer wall). In any case, as he is under force, he knows he is under acceleration. (He might also notice the planet out the window.)
The Ensign also experiences the effects of gravity, plus the effects of his shuttle engine. Indeed, he *calculates* the thrust to compensate for the gravity. He reaches the same conclusion as the Captain.
The Captain is the twin that travels.
Comment by Zachriel — February 19, 2008 @ 10:59 pm
February 19th, 2008 at 11:02 pm
Hi Oleg,
Since a reference frame origin can be chosen arbitrarily, that alone allows for "an infinitude of reference frames." Axis orientation compounds the infinity.
There is a point when arguments are made just for argument's sake.
I believe I have communicated my thoughts. I believe Minkowski and Penrose have communicated their thoughts.
If you want to hold "special relativity" in a special place for whatever sentimental reasons, be my guest.
The 4D spacetime geometry is solid. The math works even if you don't take the time to look at it. And, frankly, it doesn't matter to me what is "commonly accepted" or not. If I don't understand it, I am not about to let others, no matter how smart they are, do my thinking for me.
In a follow up comment you wrote…
Now we are getting somewhere, but unfortunately this is sounding desperate.
Was I completely wrong about my Twin-on-Twin hypothetical too? All the changes in inertia are done. How do you rationalize the time difference between the twins using only special relativity?
You know full well why I said I would move perpendicular. There would be no moving away or towards the pulsar being used for testing.
BTW, it doesn't matter if the pulsar is moving away. We would be looking for increases/decreases in time. As long as we test by moving perpendicular, the red-shift due to the pulsar moving would be the same for all measurements.
And as with all real world things, "there is always room for improvement."
As for the axis, I can declare my origin wherever I want as long as it isn't moving with me.
I thought you didn't want to go in circles? I got the impression we had already pretty much agreed on the basics. I was trying to move on to the QM part.
If you look at the experiment I linked to…
"In this experiment, a single photon is aimed at the double-slit."
The single photon split in half-silvered mirror and bounced all over the place. But, in Minkowskian spacetime, the distance is ZERO. There is no mystery as to how the photon can be in superposition in both space and time if 4D spacetime is considered really real.
Comment by Thought Provoker — February 19, 2008 @ 11:02 pm
February 19th, 2008 at 11:21 pm
Hi Zachriel,
I have to admit, I hadn't thought of the his-shoes-feel-too-tight argument.
Yes, the Captain and Keiths can calculate the right answer. So can I by using Schwarzschild Geometry.
I'm curious as to your answer to the two twins coming at each other in space ships with different time dialation.
Comment by Thought Provoker — February 19, 2008 @ 11:21 pm
February 20th, 2008 at 8:28 am
TP,
This program, not just its particular implementation, is doomed from the start. When you look "the time axis of our universe" you are attempting to find the frame of absolute rest, that's what your words mean. Such a frame doesn't exist. If you look to the far corners of the universe, we find that it is expanding: everything is moving away from us, the farther away, the faster. So you can't be at rest with respect to all of them.
It doesn't matter whether it's two photons or one. I am talking about Minkowski distances associated with two photon worldlines. The distance (I'll call it the interval as is the habit in physics) is strictly zero along a null geodesic. So the interval is zero between any two points along an uninterrupted light ray in spacetime. However, when you take two points on different light rays, the interval between them is generally nonzero even if they emanate from a single point. The same applies to a single light ray bouncing back and forth between two mirrors. The interval is zero between two points within a single lap, but it is nonzero (and timelike) when you take points on two different laps.
Comment by olegt — February 20, 2008 @ 8:28 am
February 20th, 2008 at 9:13 am
Hi Oleg,
You wrote…
We have a bona-fide difference of opinion.
From the link…
"Time 1. The entangled pair leaves either region A or region B of the crystal. The signal photon heads off to detector D0, and the idler photon heads off to the interferometer.
Time 2. The signal photon is registered and scanned at detector D0 according to its position. This information (the position of the signal photon upon "impact" at D0) is sent on its way to the Coincidence Circuit.
Time 3. The idler photon reaches the first pair of beamsplitters, BSA, BSB. There, QM makes a choice which direction the idler photon will go "“ either to detectors D3, D4; or to the quantum eraser BS and on to detectors D1, D2.
Time 4a. If the idler photon is shunted to detectors D3, D4, it is detected with which-path information intact. Then and only then do we know which-path information for its twin signal photon that already has been detected, scanned, registered and recorded at D0.
Time 4b. If the idler photon passes through to detectors D1, D2, it is detected with no which-path information (the which-path information having been "erased" at BS).
If I am following your logic, you seem to agree the "interval" between time 1 and time 2 for the signal photon is zero.
And the "interval" between time 1 and time 3 for the idler photon is also zero.
Then depending on the situation, the "interval" between time 3 and time 4a or 4b is also zero for for the idler photon.
Summing all these zero intervals would seem to me to result in a total "interval" of zero. Reducing all the complex light rays to a single point in 4D spacetime.
That seems to be what Penrose is saying here…
"…in twistor theory, a light ray is defined as a single point in light-ray space, and a space-time point P is represented by the celestial sphere's worth of light rays through P…"
I thank you again for the Penrose link. Note, I am not trying to argue from authority. I just want to confirm what Penrose is implying by his Twistor Theory along with looking for holes in his logic.
So, do you agree that Penrose's Twistor Theory implies this (even if you disagree with it)?
Then, assuming you still feel the total interval is non-zero, am I to presume your concept of light ray "interval" is significantly effected by traveling through a prisms or half silvered mirrors?
Comment by Thought Provoker — February 20, 2008 @ 9:13 am
February 20th, 2008 at 9:33 am
TP,
This is where you are making an error.
Take two vectors a and b in a Eucledian space and add them to form vector c=a+b. The length of vector c does not equal the sum of the lengths |a|+|b|.
The same goes for Minkowski space: the length of a sum of two vectors is not the sum of lengths. If you find that strange, work out the following example in a simplified Minkwoski space with one spatial coordinate x and time t. Two photons are emitted at the origin, x=0, t=0, in opposite directions. One thus travels along the line x=+ct, the other along x'=−ct'. It's easy to check that their Minkowski distances from the point of emission are always zero. However, their distance from each other is never zero, except when both are at the origin. Indeed, the relative coordinate Δx=x−x' = c(t+t'), while relative time is Δt=t−t', so that the interval is 2c times the geometric mean of t and t'.
Comment by olegt — February 20, 2008 @ 9:33 am
February 20th, 2008 at 10:33 am
TP can't go one conversation without letting things turn alittle blue with his topic choice.
Comment by Doug — February 20, 2008 @ 10:33 am
February 20th, 2008 at 11:18 am
Hi Oleg,
You wrote…
Thank you for explaining your view point, I will modify my explaination accordingly.
Apparently we can agree that light ray path lengths from the "…point of emission are always zero". Which means quantum entanglements can be explained as happening at the point of emission even though it looks like a backwards reference in time.
Would you agree that a light ray bent by a gravity well still has a zero path length back to the point of emission?
Would you agree that a light ray bent by a prism still has a zero path length back to the point of emission?
Surely the light ray going straight through a half silvered mirror still has a zero path length back to the point of emission. How about the part of the light ray that is reflected by the half silvered mirror?
I suggest I could show the integration (summing) of the path length of the reflected light ray still provides an answer of zero length.
For this reason, I think there shouldn't be any problem with seeing the A Delayed Choice Quantum Eraser quantum experiment is demonstrating quantum effects are interconnected (at least via the point of emission).
Comment by Thought Provoker — February 20, 2008 @ 11:18 am
February 20th, 2008 at 11:26 am
Hi Doug,
Yea, I thought about that after it was too late to edit it.
Leave it to you to not only think about it, but to say something too.
Comment by Thought Provoker — February 20, 2008 @ 11:26 am
February 20th, 2008 at 11:32 am
TP,
Yes, the wordline is still a null geodesic.
No, light is traveling at a speed slower than c.
The worldline with a reflection is not a null geodesic. The math is almost identical to my example, except that you get a timelike interval instead of a spacelike one.
No. As I have said a number of times, the length of a vector sum does not, in general, equal the sum of the individual vectors' lengths. This isn't legitimate math.
Comment by olegt — February 20, 2008 @ 11:32 am
February 20th, 2008 at 11:57 am
As far as I know, with respect to the Aether, the Lorentz-Fitzgerald space-contraction transformation was originated as an explanation for the results of Michelson-Morely in order to preserve the notion of Aether.
Even when studying Special Relativity, we use the Lorentz transformation.
Lorentzian relativity is Aether based, and will agree with most of Einstein's relativity. So I found it kind of funny we actually use an Aether-inspired transformation to work out problems in Einsteinian relativity.
Here is an article on Lorentzian Relativity.
I thought van Flandern made some decent arguments in favor of Lorentzian relativity here http://metaresearch.org/cosmol...
Then there is the possibility of Ritzian Relativity (Ritz was Poincare's student).
I am curious if there are experiments which might favor one relativity over another. Ritz was supposedly disproven by de Sitter, but I'm not so sure.
I have no set view on who is right at this time….
Robert Fritizius has suggested if there are experiments that have demonstrated Ritzian relativity, the results may be classified….
All this to say, I'm not so sure we have complete closure on anything yet….
Comment by Salvador T. Cordova — February 20, 2008 @ 11:57 am
February 20th, 2008 at 12:50 pm
Good to hear from you Salvador. How are things going?
Comment by Bradford — February 20, 2008 @ 12:50 pm
February 20th, 2008 at 1:20 pm
olegt:
TP, olegt et. al., positive comments are rarer than the more common negative ones so I thought it worth mentioning that this exchange has been both informative and entertaining. It also looks free of rancor (hope I didn't overlook something). Good contributions olegt.
Comment by Bradford — February 20, 2008 @ 1:20 pm
February 20th, 2008 at 2:13 pm
Hi Bradford,
I agree, this exchange has been positive IMO.
We may be skating the edge of frustrations but that isn't unusual when I am involved with discussions.
However, I hope this has been free of rancor.
I hope I'm not being too frustrating and thank Oleg for his patience.
I would like to think this has been helping people get a better understanding of some of the basics behind Cosmology and Quantum Mechanics.
For example, how many people here knew the clocks in GPS satellites run faster than those on Earth (contrary to what Special Relativity would suggest)?
Comment by Thought Provoker — February 20, 2008 @ 2:13 pm
February 20th, 2008 at 3:43 pm
Hi Oleg,
Let me echo Bradford's compliment and thank you for your continued contributions.
You wrote…
…and…
Unfortunately, I am at work and don't have the time or resources (Penrose's books) to quote Penrose on this. However, I am pretty sure that Penrose is clearly summing partial paths (ds) in order to calculate the path length.
In his description of the geometric solution to the Twin Paradox (Penrose calls it the Clock Paradox) he sums the two paths of the traveling twin to determine the path length.
It looks to me, for his Twistor Theory, Penrose is considering all paths from the point of emission to the point of observation, including those that go through prisms and bounce off of mirrors.
This doesn't automatically make Penrose right.
I just want to separate disagreements with Penrose from misunderstandings on my part.
Comment by Thought Provoker — February 20, 2008 @ 3:43 pm
February 20th, 2008 at 4:08 pm
TP,
Let me again use the analogy with a Euclidean space. You can travel in a car from town A to town B. The path length of your trip is not equal to the distance between the cities, unless the road is a straight line. To calculate each, you can divide the trip into small and approximately straight vector segments. The distance is the length of the sum of the segments. The path length is the sum of the lengths of the segments. The two results are not the same.
Back to Minkowski space. You said at one point in this thread:
Spacetime separation is the distance between two points. It's computed by summing the 4-vectors first and taking its norm second. The result is a nonzero interval, spacelike for two photons emitted simultaneously from a source and timelike between different points on the worldline of a photon bouncing between mirrors.
Comment by olegt — February 20, 2008 @ 4:08 pm
February 20th, 2008 at 4:25 pm
Even from the fog of only having read freshman physics, and that over 25 years ago, I remember that Special Relativity has nothing at all to say about the effects of time dialation to objects under acceleration, like an orbiting satellite.
Comment by One Brow — February 20, 2008 @ 4:25 pm
February 20th, 2008 at 5:52 pm
Hi One Brow,
I am not sure what you were intending with your comment. I am guessing what you meant to say is something like Special Relativity didn't take into account gravitational effects.
It would be possible to set up a space ship to move in a circular pattern that has the same radius and speed as a geosynchronous orbit. Of course the ship would require constant thrust (i.e. constant acceleration).
If you did that in flat Minkowskian space, then you could calculate the time effects using Special Relativity similar to calculations in the Twin Paradox.
In this situation the stationary twin's clock would run faster than the traveling twin. IOW, the stationary twin would be growing old while the traveling twin stayed young.
Therefore, if Earth's gravity well didn't curve spacetime, the motion of the GPS satelites would result in Earth's clocks appearing to run faster, not slower. The fact that the opposite appears to be the case provides significant evidence that 4D spacetime actually exists and can curve.
I provided the calculations in this comment.
Comment by Thought Provoker — February 20, 2008 @ 5:52 pm
February 20th, 2008 at 10:33 pm
Hi Oleg,
I am trying to adjust my terminology based on your responses. I should not have used the term "distance". I should have stayed focused on path lengths.
Apparently we generally agree that the path length from photon emmision to detection is zero.
We disagree over what constitutes an exception to this.
Can I take it you have no objections to considering the path lengths involved in a basic light ray dual slit experiment as being zero?
If you will allow me to take the next step and suggest that a basic Wheeler Delayed Choice experiment (no prisms, no mirrors) would also have zero path lengths…
…with this view, the quantum entaglement of the light rays could be seen as two zero path length (i.e. points) in 4D spacetime coexisting at the emission location (also in 4D spacetime).
Let's try to add some mirrors, ok?
On page 420 of The Road to Reality Penrose is explaining how to calculate a path length in Minkowskian geometry for the Twin Paradox. Penrose is definately summing individual path segments to calculate the length of the entire path.
Allow me to put some numbers down for a .8 light year trip out and back traveling at .8 times the speed of light (two years for the entire trip).
ds^2 = dt^2 – dx^2 – dy^2 – dz^2
ds^2 = 1^2 – 0.8^2 – 0^2 – 0^2
+ 1^2 – (-0.8)^2 – 0^2 – 0^2
ds^2 = 0.72
ds = 0.8485 years for the traveling twin (2.0 years for the stationary twin)
If the traveling twin is a massless photon moving at light speed, then the path length becomes zero.
To me, this is the situation of a light ray bouncing off a mirror.
Comment by Thought Provoker — February 20, 2008 @ 10:33 pm
February 20th, 2008 at 11:07 pm
TP, if you are talking about the length of a worldline, that would be zero for a light ray, whether it travels in empty space or bounces once or twice off a mirror.
Now tell me what that has to do with quantum entanglement.
Comment by olegt — February 20, 2008 @ 11:07 pm
February 20th, 2008 at 11:32 pm
Again, not the Special Relativity I studied, which gave results comparing differing inertial states, not accelerating states.
Comment by One Brow — February 20, 2008 @ 11:32 pm
February 21st, 2008 at 12:37 am
Hi Oleg,
You wrote…
Good. Let's get back on track. Let me give a summary for our listening audience.
The classic dual slit experiment demonstrates what has been called "quantum weirdness". It starts out subtle but quickly becomes woo sounding.
Light will act like particles and/or waves depending on the experimental setup. It is almost like the observation itself determines which happens. An interference pattern is wave like. An even distribution is particle like.
Things got real interesting in the QM field when the technology improved enough to fire one photon at a time. The interference pattern still showed up. It is like a single photon goes through both dual slits at the same time. However, any attempts to determine which slit or slits the photon is going through results in a particle-like pattern. But when you aren't looking, the interference pattern appears.
For a long while the suspicion was that somehow the measurement method interfered with the photons. So an experiment was set up to attempt the measurement after the fact. This experiment is known as Delayed Choice.
It didn't matter. Delayed or not, attempts to measure which path(s) the photons take cause the quantum behavior to revert to particle-like.
Still not sure that the measurement wasn't effecting the results, an experiment was devised to measure the which-path information and then intentially scramble the measurement to loose (i.e. erase) the information.
This is know as the Delayed Choice Quantum Eraser
Here is a link that tries to explain the paper in layman's terms.
Generally, there is a main detector for the signal photon to check for interference patterns and three detectors (a fourth detector is implied) to detect an entangled twin photon.
The twin photon has the same which-slot information that the signal photon would have. The measurement of the twin photon is intentionally delayed (8 nanoseconds) after the measurement of the signal photon.
Which detector is used to measure the twin photon is left up to quantum chance.
If detectors 1 or 2 do the detecting then the which-path information has been "erased" and the main detector shows a wave-like interference pattern. Otherwise (detector 3 or 4) the which-path is known and the particle-like pattern appears.
BTW, the patterns are determined way after the fact by tabulating the data depending on which detector did the detection of the twin.
This provides the hard experimental data that somehow, someway, the measurement of the entangled twin photon retroactively effected the main photon.
And the big question is "How?".
I think Penrose and others suggest the logical answer comes from recognising the reality of four dimensional spacetime.
Path lengths traveled by photons in spacetime are ZERO. Penrose's Twistor Theory turns the geometry inside out by saying light rays are points, not lines, in spacetime.
The suggestion is that the quantum entanglement in this experiment comes from the photons coexisting in the same point in spacetime.
Comment by Thought Provoker — February 21, 2008 @ 12:37 am
February 21st, 2008 at 9:36 am
I'd like to see where Penrose says that light rays are points in spacetime. It's patently not the case. Zero length of a line in Minkwoski space does not mean it's a point (the metric is not positive definite).
And I'd like to see intermediate steps leading you to the final sentence.
Comment by olegt — February 21, 2008 @ 9:36 am
February 21st, 2008 at 9:56 am
Hi Oleg,
I stand corrected. I should have said a point in "light-ray space" or Twistor Space.
"The twistor viewpoint is to regard light rays as more primitive than points in space-time, so it takes "light-ray space" "” the space whose individual "points" represent entire light rays in space-time "” to be more fundamental than space-time itself. This turns out to have wide-reaching consequences.
In the normal view of space-time, two points can sometimes be linked by a light ray, which is usually represented as a line passing through the space-time. But in twistor theory, a light ray is defined as a single point in light-ray space, and a space-time point P is represented by the celestial sphere's worth of light rays through P "” in other words by a complex curve (a Riemann sphere) running through light-ray space." link
It's going to be a busy day for me. I may not get to respond more fully until this evening.
Comment by Thought Provoker — February 21, 2008 @ 9:56 am
February 21st, 2008 at 2:55 pm
It is good to visit. I wasn't expelled from JHU as I was from Baylor. There was a famous creationist who taught at JHU by the name of Lee Spetner, and in fact he taught at the Applied Physics Lab of (APL) JHU where I'm studying now. So I guess it would be a bit peculiar for me to be tossed for anything but poor academic performance (I have a 4.0 now after my first semester).
I studied introductory modern physics my first semester there which included special relativity and introductory quantum mechanics and atomic structure.
My professor last semester worked on space probes that had to deal with the effects of special and general relativity and we had to do calculations with vectors in minkowski 4-space. For example here is something from our class notes: Example of Minkowski Calculation.
We did homework problems to account for the effects of special relativity and general relativity. My professor recounted how a space probe he worked on had a peculiar anomaly in the oven controlled clocks in the space probe (which had some engineering done at JHU APL). They weren't in agreement with the predictions of special relativity. Were the clocks broken????
Well, this anomaly popped during a planetary flyby, and they realized they forgot to put in a small correction to account for the effects of gravity during the close but brief flyby….. Even though this correction has been done a buzillion times (such as in the university of Maryland experiment with clocks and airplanes), I suppose the urgency of other matters in the operation of space probes took precedence. It was a minor math error and almost amusing that something slipped through the cracks that should have been obvious. It happens….We had to repeat the calculations in class
I will not have full blown relativity until a year from now since I'm a part-time evening student and I'll be taking core grad level classes (math methods, quantum mechanics, statistical thermodynamics, electromagnetic theory, classical mechanics) before I get to the good stuff like full blown relativity and plasma physics.
Regarding Einstein's special relativity, I'm not fully convinced it is correct. Yes, most of the experiments agree with predictions of Einsteinian Relativity, but most of the experiments also agree with Lorentzian Relativity and Ritzian Relativity. In fact, the famous "gamma" symbol used in Special Relativity refers to the Lorentz-Fitzgerald space contraction, and that was an Aether-based theory!!! The neceissity of the Lorentz transformation is highly important to reconciling paradoxes in electromagnetic theory.
The Lorentz transformation allowed electrodynamics to work independent of the inertial reference frame that was chosen to make the calculations. This is highly important, because without Lorentz invariance, you would predict differing behavior of physics merely because you chose a different coordinate frame. This was highly undesirable (and obviously wrong). So thus was born the Lorentz Aether-based transformation that allowed us to find and invariance between coordinate frames and solve a paradox in electromagnetic theory.
I did demonstrated the derivation of the Lorentz Aether-inspired transformation here: Lorentz Covariance and the Creationist Maxwell's Equations. This relationship is highly improtant to physics even though the Aether was supposedly disproven by Michelson-Morely. Nay, in actuality the Lorentz transformation was partially inspired as a kludge to Aether ideas. But it works, and it got incorporated into Einstein's Special Relativity.
This transformation was central to Einstein's Relativity, but the irony is that while Einstein uses basically the same math, Lorentz had a totally different
justification for the mechanisms. One can derive all the same experimental predictions (well almost all) with Einsteinian relativity as you would with Lorentzian. In fact, most of the math is indistinguishable between the two theories. But there could be a few observations and experiments which could cause Lorentzian or even Ritzian relativity to be favored over Einsteinian relativity…
There has been a resurgence of interest in Lorentzian relativity. Van Flandern posses some experimental data that would refute Einsteinian relativity and affirm something closer to Lorentz-Poincare invariance. And last but not least, Poincare's other student, Ritz has started to come back in vogue.
I was thinking of a nice experiment which might confirm or disconfirm Ritzian relativity. Robert Fritzius has great stuff on the correspondence of Ritz and Einstein: here.
As a final note, I'll have some juicy questions for my professor of relativity. Something about Lorent-Poincarian and Ritzian relativity seemed more "right". Note the question I pondered about light switches on a train here. That's an open question to me personally which I didn't quite find the answer to in my textbooks. I think Dr. Paul Marmet had the same issues Demonstration of the Lorentz Equations without Einstein's Relativity Principles.
PS
olegt, good to see you here. I sorry I won't have the privilege of taking your condensed matter physics classes since I'm at a different campus at JHU than you….regards.
Comment by Salvador T. Cordova — February 21, 2008 @ 2:55 pm
February 21st, 2008 at 4:19 pm
Hi Oleg,
In a random search I found this paper titled Heterotic Twistor-String Theory
Thank you again for clueing me in on the recent marriage of Penrose's Twistor Theory and String Theory.
Comment by Thought Provoker — February 21, 2008 @ 4:19 pm
February 21st, 2008 at 9:56 pm
Hi Oleg,
Sorry, but a busy day was followed by a busy night. Maybe more tomorrow.
Meanwhile, here is something from Penrose that appears to be his explaination on the subject…
On Quantum Twistor Space and the Regularization of Divergences
Comment by Thought Provoker — February 21, 2008 @ 9:56 pm
February 22nd, 2008 at 12:49 am
Hello Sal,
I am unaware of any physical situation in which Einstein's special relativity and Lorentz's earlier theory would yield different results. Maybe you can point them out to us. Lorentz's theory was formulated in terms of absolute motion relative to the aether. However, the Lorentzian kinematics (which included spatial contractions of objects and time dilation) made it impossible to detect the motion with respect to the aether, in agreement with experiments of the day. The aether was thus unnecessary.
While Einstein's special relativity makes identical predictions, it is a much better theory than Lorentz's. It declared all inertial reference frames equally good and postulated that the speed of light is the same in such frames regardless of the speeds of the source and the observer. These are experimental facts verified to a very high precision. It then follows that time isn't absolute: stationary and moving clocks do not agree.
Sure, one could use Lorentz's theory to obtain the same results. And if Einstein hadn't come along, that theory would have dominated for a while. And that would be sad because no one (including Einstein) would be able to guess the equations of general relativity by looking at Lorentz's theory. It just doesn't have the right look for that: no 4-vectors, no metric.
In contrast, Ritz's emission theory is distinct from special relativity in that it makes different predictions in some situations. It has been tested in the early 1920s, was found to be inconsistent with the experimental data, buried, dug out in the 1960s, retested, pronounced dead and buried again. Anyone interested in the details will find them in this recent review: A. A. Martinez, Ritz, Einstein, and the Emission Hypothesis, Physics in Perspective 6, 4-28 (2004). doi:10.1007/s00016-003-0195-6
Comment by olegt — February 22, 2008 @ 12:49 am
February 22nd, 2008 at 8:15 am
You were expelled from Baylor?
Comment by Bradford — February 22, 2008 @ 8:15 am
February 22nd, 2008 at 10:12 am
Stay away from crackpots, Sal. Van Flandern has zero credibility. At some point he claimed that Einstein had fudged his theory of general relativity to match the precession of Mercury's perihelion. This is patently untrue: general relativity has no free parameter with which one could do that. The most charitable interpretation of this is Van Flandern does not know what he is talking about.
See this story in Salon: Did Einstein cheat?
Comment by olegt — February 22, 2008 @ 10:12 am
February 22nd, 2008 at 1:04 pm
Not officially, but Robert Marks (based on a referral by Bill Dembski) offered the equivalent of a $40,000 tuition and stipend package for me to get an MS in Electrical and Computer Engineering. I was slated to work specifically for the Evolution Informatics Lab that was eventually closed down. It would have been real bad if I ended up at Baylor only to see the lab shut down, not to mention I'd probably be walking around campus with a bullseye painted on me.
I had applied to Hopkins, and I was privy to a lot of what was going on in Baylor behind the scenes, and just before all the press broke out regarding Baylor, I had already decided to go to Hopkins.
So technically, I wasn't on the boat when it sank. There was at least another grad student slated for the spot in Baylor had I not persued it (it was hard to turn down my opportunity at Hopkins). It was that un-named grad student that was mentioned in the press releases….So I and that other grad student were effectively "expelled" (to quote Ben Stein) because the Evolution Informatics Lab was shut down….
Comment by Salvador T. Cordova — February 22, 2008 @ 1:04 pm
February 22nd, 2008 at 1:08 pm
I had not heard that story Salvador. Incidentally I read Spetner's book years ago. Is he now retired?
Comment by Bradford — February 22, 2008 @ 1:08 pm
February 22nd, 2008 at 1:39 pm
Hello Olegt,
When I learned the postulates of relativity theory in class, there was not explicit mention of whether information between objects can be exchanged faster than the speed of light. But I have heard exchange of information between objects at a rate faster than the speed of light would be a violation of SR. Is this correct?
We even did Minkowski space-time diagrams in class to determine if objects could or could not be causally connected….
However, I heard discussion of objects being in causal contact requiring instantaneous connection. I think EPR (Einstein Podolsky Rosen) touched on this.
Also, if I move an object, does its gravitational field not have an instantaneous effect on objects around it, thus the surrounding objects have causal connection faster than the speed of light? Is there a corresponding issue with coulomb forces acting at a distance? In elementary Electro-Dynamics, we modeled coulomb forces (say from a point charge) as acting instantaneously. Is it simply a matter that maybe I need a little more advanced knowledge in Electromagnetic Theory to see that the field generated by a coulomb force from a moving point charge will not be instantaneously propagated along with the point charge…Say I have a stationary point charge and it is accelerated to a velocity V, and there is some point in space a modest distance away, will that point in space instantaneously experience a change in the electric field or will there be a delay before that point in space experiences a change in electric field due to the recently accelerated charge? I never got around to asking my E&M professors this question as an undergrad, I was too busy just trying to learn the basic concepts to bother them with this…so maybe a little more study on my part will be the cure.
But anyway, those were the questions in the back of my mind…
Thank you for the link. For the record, the very first day of class an allusion to disproofs of Ritzian relativity was made (de Sitter's work), and Ritzian ideas were presented as a refuted theory in class. Lorentz relativity was presented as a "kluge" to the Aether. I mention this just to reassure you that my teachers at JHU-APL are teaching me mainstream science (not van Flandern)…:smile:
regards,
Salvador
Comment by Salvador T. Cordova — February 22, 2008 @ 1:39 pm
February 22nd, 2008 at 2:30 pm
Sal, please be careful redefining the word "expelled".
Bradford on another thread:
Comment by Raevmo — February 22, 2008 @ 2:30 pm
February 22nd, 2008 at 5:42 pm
The historian Paul Johnson wrote that redefining words was a common strategy of 20th century tyrants and used as a means of control. Looks like the strategy persists into the 21st century.
Passen Sie auf Raevmo.
Did you note the word "eventually" Raevmo? Obviously this was an evolutionary process which resulted in the purposeless removal of any chance that Salvador would attend Baylor.
Comment by Bradford — February 22, 2008 @ 5:42 pm
February 22nd, 2008 at 7:14 pm
Bradford,
My apologies for the digression regarding relativity. Regarding Spetner, he is retired. You'll see Nobel Laureate Anfinsen (also from JHU) giving an endorsement for Spetners book on the back cover!
Also, Dr. Paul McHugh, a distinguished scientist and medical doctor at Hopkins came out in 2004 in favor of allowing Darwin to be criticized.
JHU has various schools, and JHU-APL caters to the Defense and Aerospace Industry. Engineers and Physicists in those industries are notorious for being more likely to be creationists and ID sympathizers, so it's no big surprise someone Spetner could make a home for himself at JHU-APL. JHU-APL helps build spaceships and other high tech things. It is mostly free from the origins controversy in biology. However, on the main campus (not too far away) in Baltimore, things might be different.
Not too long ago a professor from Hopkins had some choice words in a letter to Michael Behe. And in 2006 there was an "ID" course (I use the term loosely in that it was probably anti-ID course) in the Philosophy Department Science vs. Intelligent Design, Philosophy 150.439.
So in the spirit of academic freedom we have professors like Spetner arguing for ID and others against it….
There are still several creationists and ID sympathizers at Hopkins. [names withheld to protect the guilty].
Comment by Salvador T. Cordova — February 22, 2008 @ 7:14 pm
February 22nd, 2008 at 7:47 pm
Revisiting olegt's question about what will distinguish SR (einstein) from LR (lorentz) or any other relativity since experimentally both are for the most part indistinguishable.
After pondering the issue, there are various kinds of fields predicted by Maxwell's equations. We have the "simple" fields predicted by the 1st of Maxwell's equations, otherwise known as The Divergence Theorem and then complex time-varying fields such as those associated with Maxwell's 4th equation (Ampere's circuital law) which predicts the radio waves Hertz became famous for and things like Bremsstrahlung.
So an accelerating charged particle not only has electromagnetic radiation (like bremsstrahlung and radio waves) associated with it, but it has the basic electrostatic field surrounding it, and that field moves lock step instantaneously with the particle. [Any one correct me if I'm mis-interpreting the divergence theorem]
If would seem then, that if we had sufficiently good detection of the electrostatic field (E-field) based on the divergence theorem, and since movement of the field is instantaneous with respect to the position of the point source, that in principle, movement of the point source creates a "transmission" of information instantaneously to any point within the field defined by the divergence theorem. But this would seem to violate SR (maybe?) or at least bend the spirit of its postulate. This sort of faster-than-light communication seems possible in LR, and LR would not violate the measured speed limits on light for things like radio waves and bremsstrahlung radiation.
The discussion of SR and LR deal with reference frames with constant relative velocity. GR (general relativity) deals with reference frames accelerating relative to each other, and that is way beyond my current level of knowledge…
Comment by Salvador T. Cordova — February 22, 2008 @ 7:47 pm
February 22nd, 2008 at 8:57 pm
Bradford:
Um, was soll das heissen? Weshalb schreiben Sie Deutsch?
Yeah. But if you get offered a job somewhere, and the outfit that offers the job goes bust before you can start, that hardly justifies the claim that you got expelled. Regardless of why the outfit went bust. Or am I missing something?
I appreciate the sarcasm, but what are you really trying to say?
Comment by Raevmo — February 22, 2008 @ 8:57 pm
February 22nd, 2008 at 9:09 pm
Obviously this was an evolutionary process which resulted in the purposeless removal of any chance that Salvador would attend Baylor.
When Baylor decided on a course of action that kept an intellect like Salvador away the message was: No intelligence allowed. Go see it when you get the chance. You can bet it will be discussed at your favorite ID blog.
Comment by Bradford — February 22, 2008 @ 9:09 pm
February 22nd, 2008 at 10:59 pm
No. Superluminal travel does not contradict the postulates of special relativity. However, it creates another problem: coupled with relativistic kinematics (in the form of the Lorentz transformation), it violates causality. A bullet fired at a superluminal speed in one reference frame will strike its target prior to being fired in another, moving frame. It's the violation of causality that forbids travel or transmission of information at a speed greater than c.
No, it is well known that quantum entanglement (of which EPR gave the first example) does not enable instant communication.
No, this is wrong. There is not enough information in a single Maxwell's equation to determine the electromagnetic field, except in very special cases such as an electric charge at rest. In that case the missing information is supplied by additional considerations (spherical symmetry and the absence of time dependence). Anyway, even though a static electric charge is surrounded by a spherically symmetric electric field, it does not mean that this electric field will move rigidly along with the charge. That would amount to the superluminal transmission of a signal, which we know would wreak havoc with physics.
To determine the EM field of a charge that begins to move one has to work hard and use all of Maxwell's equations. The standard method uses retarded potentials (scalar φ and vector A). A quick look at the formulas shows that changes in the EM field propagate at the speed of light c. Thus, if a charge x meters away starts to move, we won't find out until x/c seconds later. This isn't entirely surprising because Maxwell's equations are compatible with both special relativity and causality and thus don't permit a superluminal transmission of signals.
Comment by olegt — February 22, 2008 @ 10:59 pm
February 22nd, 2008 at 11:30 pm
Hi Oleg,
Have you see those T-shirts with Maxwell's equations on them?
"And God said…and then there was light"
I'm not bringing this up for its religious significance.
It is the ontology.
When I was getting my BSEE (a long time ago) I was struggling with understanding Maxwell's equations. It wasn't the math, it was the concept. The logic was too circular (Collapsing E fields generate H fields that collapse and generate E fields).
I was struggling with the understanding why any of it happened.
Then it dawned on me, it happens because it can.
To me, physics is about trying to understand what can happen.
We don't need to actually see Black Holes to know they exist. As long as they can exist, they do.
So, for me, the answer to understanding quantum entanglement in experiments like the Delayed Choice Quantum Eraser is figuring out how it can happen.
I don't have enough training to describe and defend the details. It is hard enough just trying to understand things like this Penrose lecture.
Did you take a look at it. I think it is rather clear that Penrose is attempting to use his Twistor Theory to describe how non-local quantum effects are possible in our universe.
If it can happen, it does.
P.S. Thank you again for your patience. I think your comments to Salvador have been informative. I will try to do my part from an engineering view in my next comment to Salvador. Let me know what you think.
Comment by Thought Provoker — February 22, 2008 @ 11:30 pm
February 22nd, 2008 at 11:37 pm
TP, you were asking the wrong question. Physics doesn't deal with the why, it deals with the how.
Again, I disagree. Theoretical physicists (Penrose and myself among them) can dream up anything they want, as long as it's mathematically consistent. But their dreams are checked against reality by experimentalists and rejected most of the time. Such is life.
And by the way, we have experimental evidence for the existence of black holes.
Comment by olegt — February 22, 2008 @ 11:37 pm
February 23rd, 2008 at 12:08 am
Hi Salvador,
Let me see what we can do engineer to engineer.
I assume you are familiar with Inertial Measurement Units (IMU).
Now imagine IMUs that simply measures the length of a path taken. If we put one in a box and mailed it to ourselves we could find out the length of the route it took.
Now imagine the situation where we mail one IMU from Chicago to Seattle while taking another IMU in a car that we drive to Seattle. We meet up with our mailed package in Seattle. We check the IMUs and find the path lengths are different. Our IMU shows the path we took was shorter (the mailed package went through a distribution center).
Now imagine an IMU that measures path lengths in four dimensional space-time.
I find it easier to think about this if I normalize the space-like dimensions to things like light-years, light-seconds and light-nanoseconds. A light-nanosecond is about a foot.
The 4D IMU I am describing turns out to act just like a standard clock.
The Chicago to Seattle trip would be analogous to the Twin Paradox in 4D space-time.
The situation with GPS satellites is a real-world, everyday example that shows two IMUs/Clocks measuring different path lengths. I provided the numbers in a previous comment.
If you need me to fill in any of the details, I could do that, but I think with your engineering back ground you should be able to plug in the values and come up with the final answer yourself.
A final answer that is consistent with real world observations.
Comment by Thought Provoker — February 23, 2008 @ 12:08 am
February 23rd, 2008 at 12:24 am
Hi Oleg,
I offered my comment to explain my thought processes. I am not a physicist. I am just an engineer trying to make sense of things.
You wrote…
Good. I think I am getting a handle on what Penrose dreamed up to explain observations in the Delayed Choice Quantum Eraser experiment.
What is your explaination?
Comment by Thought Provoker — February 23, 2008 @ 12:24 am
February 23rd, 2008 at 9:17 am
TP,
I am not sure I understand your position, so feel free to correct me if I'm wrong.
Double-slit experiments demonstrate a wave-particle dualism of quantum mechanics. They demonstrate that a photon does not go through one of the slits, it goes through both. (In classical physics, particles don't do that, waves do.) We can figure out through which one but that requires an interaction with the photon and that interaction affects the observed interference pattern. Wheeler's delayed-choice variant just illustrates this situation more starkly.
What I am not sure about is why you think that Penrose is attempting to "explain" Wheeler's thought experiment. His twistor math has nothing to do with the wave-particle duality. In the first slide of that lecture he points out that a wavefunction is not a physical observable (because otherwise the collapse of a wavefunction in an experiment would imply superliminal propagation of a physical object). The rest of the lecture explains how to do mathematics with twistors and how to translate the standard quantum-mechanical description of a massless particle in the most general spacetime into the twistor language.
Don't blame relativistic effects, TP. The same strange quantum phenomena are also observed with slowly moving particles, e.g. electrons. Relativity alone can't explain it.
Comment by olegt — February 23, 2008 @ 9:17 am
February 23rd, 2008 at 1:36 pm
Oleg said:
I notice a preference for particulate (physicalist) descriptions… "(because otherwise the collapse of a wavefunction in an experiment would imply superliminal propagation of a physical object)."
Does Oleg consider field quanta to be "physical objects?" Does a physical object of light (photon) GAIN a 'worldline' when it collapses, that it didn't have as wave? What is included in that 'worldline'? The entirety of extended field interactions in spacetime?
If so, the mystery is solved.
Comment by Joy — February 23, 2008 @ 1:36 pm
February 23rd, 2008 at 1:57 pm
Hi Oleg,
Thank you for your response and please feel free to correct me as you see fit (that is kind of the idea here).
First, it looks like we are past having the Delayed Choice be a "thought experiment". The "interaction affects the observed interference pattern" AFTER the photon would have made it's contribution to the interference pattern.
And with the Quantum Eraser, the "interaction affects" that would normally cause the interference pattern to go away doesn't because the which-path information is intentionally scrambled AFTER THE FACT.
What is shone "more starkly" is that non-locality occurs in both space AND time. I am suggesting that relativistic space-time appears to be very much involved in the experiment I have referenced.
I noticed you haven't provided a counter-explanation yet.
I recognize that this happens with things other than light. Fairly massive BuckyBalls would be a good example and, hopefully, we will get to that explanation soon enough. But, for now, I am suggesting that light provides a more intuitive feel for what I believe Penrose is suggesting.
The 45 minute presentation by Penrose was titled On Quantum Twistor Space and the Regularization of Divergences and was part of the two and a half day workshop titled From Twistors to Amplitudes
In layman's terms, what would you say this Workshop was about?
I suggest it was focused on exploring how Penrose's Twistor Theory can explain the "amplitudes" and "regularization of divergences" of what we call "particles" acting in accordance with what we call "Quantum Field Theory".
As an engineer I have often irritated PhD-types with my attempt to over-simplify things. While their irritation is often justified, I tend to need to boil it down to the basics so I can understand it.
An example of an over-simplification is that I view the modern Copenhagen Interpretation as saying their is no such thing as particles; everything is part of a wavefunction.
That would be similar to me saying there is no such thing as sonic booms, only parts of wavefunctions in air. A detailed-oriented person would be tempted to argue with me that sonic booms do exist, but that isn't the point of understanding what sonic booms are.
It is becoming obvious that particles are like air bubbles trapped under a sticky plastic sheet. The bubbles can be be pushed around and appear to "move". However, if you try to quicky smash a bubble some interesting things can happen. One possibility is another bubble pops up somewhere else.
I suggest the quantum equivalent to this would be a quantum tunneling (you can pity the poor PhD-type that had to explain how Tunneling Diodes worked to this BSEE).
So the Delayed Choice Quantum Eraser experiment starts looking like a complicated whack-a-mole game in 4D spacetime. It is complicated by the fact that more than one mole can pop up and things can appear to happen retroactively.
The whack-a-mole game does have some strict rules. One of which, is that no causal paradoxes are allowed. I think Penrose is explaining some of the more nuanced rules with his Twistor Theory.
Starting on page 964 of The Road to Reality, Penrose writes…
Whether or not I have caused you to become a "Penrosian", have I convinced you yet that Penrose, himself, feels his ideas are more fundamentally significant than just "abstract math"
To me, Penrose's partnership with Hameroff and Orch OR makes perfect sense, if he actually believes this is really real. Understanding the role of consciousness was needed to complete the picture for Penrose.
But I am getting ahead of myself. The current subject was Penrose's belief and explanation for the Delayed Choice Quantum Erasure experiment.
I think I understand an oversimplified version of what Penrose is suggesting.
Do you have a counter offer?
P.S. to those interested, The Road to Reality is available for $16.50. It is over 1000 pages long of more math than any sane person would want to read. But I think it provides a good foundation to what looks like may become the next big Science buzz word, Twistor String Theory.
Comment by Thought Provoker — February 23, 2008 @ 1:57 pm
February 23rd, 2008 at 2:11 pm
Hi Joy,
I am glad you decided to join in the conversation. I think you are going to the heart of the matter, which is… err… um… MATTER!
Giving up the materialistic viewpoint is hard, even for some ID proponents.
Comment by Thought Provoker — February 23, 2008 @ 2:11 pm
February 23rd, 2008 at 3:38 pm
Hi, TP. I'm busy during the week (and as spring approaches, on the weekend). Besides, the ideological commitments of individual physicists don't interest me much. It seems like a non-issue to me, the positivists are just wrong.
Treating particle interactions as if they involve 'real' objects is a mere convenience. Light has no 'worldline' (until it's absorbed? What does it become then?) is just mind-spinning. Do particles with mass have 'worldlines'? What's mass? Don't talk to me about 'virtual' particles, they're just another way of thinking about things, and if we're thinking about them consciousness is intimately involved… Is consciousness a 'real' thing? A "physical object?" What's its quanta? How much mass does it contain? What's mass?… on and on and on, endlessly circular.
It's way too easy to get stuck on terminology that serves no function other than to disguise interpretational prejudices, which count for nothing 'real' despite insistence otherwise by all consciousness involved. What the heck can we agree upon as being 'real'? And why do the disagreements always boil down to ideology?
Makes my head hurt. What is illusion, what is 'real'? (or, perhaps more illustrative, where is the "center of the universe?")
Comment by Joy — February 23, 2008 @ 3:38 pm
February 23rd, 2008 at 3:51 pm
Hi TP,
It looks like you're offering me to read The Road to Reality and argue directly with Penrose. We can certainly switch to that mode, but I'll have to get the book first: I can't rely on brief excerpts that you provde.
Comment by olegt — February 23, 2008 @ 3:51 pm
February 23rd, 2008 at 4:19 pm
Hi Joy,
I should be too busy during the week to comment but I don't seem to be able to help myself.
As usual, I agree more than disagree with your last comment. The terminology and semantics get in the way of trying to discuss ideas. It gets irritating when it seems like an argument gets wrapped around words instead of ideas.
I find arguing motivates me into looking deeper. I didn't know about Twistor String Theory until Orel pointed it out to me. Did you?
It is rather interesting to see how people are appear to be relieved at giving up the extra dimensions that everyone knew had an artificial feel about them.
I like the idea of getting back to four spacetime dimensions even if the four dimensions are complex numbers. I have no problem with the thinking of a complex number being as being one dimensional. I am used to thinking in terms of e^jwt as an electrical engineer (we use "j" instead of "i" for square root of -1).
BTW, are Matti's eight dimensions complex, or could they be thought of as four times the two dimensions of complex numbers?
At any rate, I am encouraged that after forty years, it looks like Penrose's Twistor Theory may become the next "new" way of thinking about the ultimate unified reality.
Comment by Thought Provoker — February 23, 2008 @ 4:19 pm
February 23rd, 2008 at 4:22 pm
Joy, you seem thoroughly confused. A particle has a worldline in classical physics (here classical means not quantum; I will speak of relativistic mechanics as a classical theory). In quantum mechanics worldlines are somewhat blurred because of Heisenberg's uncertainty relation, Δx Δp > h/2π. But this kind of blurring is not unique to quantum mechanics: the same happens to waves.
Geometrical optics operates with a concept of a light ray, which is a close analog of a worldline in spacetime. Ray optics provides excellent means of figuring out how light propagates: high-precision optical lenses are designed on the basis of ray optics. It was discovered later that light consists of waves. Light rays become blurred when they are led through a small opening. The phenomenon is known as diffraction and it leads to a similar relation between the uncertainties of the transverse coordinate of a ray and the angle at which it travels, Δx Δθ > λ/2π, where role of Planck's constant is played by the wavelength of light λ. The blurry nature of light rays doesn't force physicists to throw up their hands in the air. We understand how to deal with diffraction, interference and other wave phenomena. I'm sure you still remember the names of Huygens, Fresnel and Fraunhofer.
Likewise, we know how to deal with the quantum blurriness of worldlines. The apparatus of wavefunctions accomplishes that. If you don't like wavefunctions, there is Feynman's path-integral approach, which is in essence a generalization of Fresnel's superposition principle. Per Feynman, a particle travels from point A to point B along all possible worldlines. Each worldline (a path) is given a particular complex amplitude and all of the amplitudes are added to obtain the total. Like in wave optics, it turns out that most of the paths cancel out and only those which are closest to the classical trajectory contribute significantly, hence a slightly blurred classical worldline. Note that Feynman's theory is not just hand waving, it is a very concrete strategy for calculating the outcome of a physical experiment. Once you add the tactics (a recipe for computing the amplitude for a particular path, which we also have), you can compute things and compare them to an experiment. And you know what? It works with an astonishing accuracy.
If by understanding of the quantum weirdness you mean a way of reducing it to our familiar classical experiences, forget it. We don't have it and won't have it. TP, that applies to you as well.
And Joy, it's hard to tell what you mean by saying that virtual particles are "just another way of thinking about things." What things in particular?
Comment by olegt — February 23, 2008 @ 4:22 pm
February 23rd, 2008 at 4:24 pm
Hi Oleg,
You wrote…
I would be very much interested in having you do that.
I could even be patient in waiting for you to formulate a response.
One of the things I would be interested in is a compare and contrast of different explainations for the results of quantum experiments like Delayed Choice Quantum Erasure.
Comment by Thought Provoker — February 23, 2008 @ 4:24 pm
February 23rd, 2008 at 4:36 pm
TP, are you sure Penrose does that? Can you point me to a particular passage?
Comment by olegt — February 23, 2008 @ 4:36 pm
February 23rd, 2008 at 4:57 pm
Hi Oleg,
page 578 of The Road to Reality.
I think I could probably find a direct reference where Penrose talks about Wheeler's Delayed Choice experiment but I don't think it is in The Road to Reality. I don't remember anything from Penrose about the Quantum Erasure, but I suggest that isn't significant since it is clear Penrose considers all photons to be AUTOMATICALLY entangled in the single wavefunction that is our universe.
Comment by Thought Provoker — February 23, 2008 @ 4:57 pm
February 23rd, 2008 at 5:05 pm
TP, that passage from Penrose is entirely in the realm of standard QM.
Comment by olegt — February 23, 2008 @ 5:05 pm
February 23rd, 2008 at 5:28 pm
Oleg:
LOL!!! Oh, my. Know what a "supercrystal" is? Do you know how manufactured crystals can be rated at .05 or .01 angstroms? How do they DO that? What'll they think of next? "Virtual" crystals? Do you really believe any of it's "new?"
But yeah. I do know the various cool attributes of cut glass (which is not a periodic crystal). Even know that Heisenberg got stumped on his PhD orals by being asked a question on optics that he didn't know the answer to, and how his chagrin "changed the world."
Please answer the questions from your POV. What does the 'zero worldline' become when the measurement is made (and the "physical object" becomes 'real')? Where was the 'worldline' before it became 'real' (space? time? spacetime?) and what does it include?
THEN what happens to it?
Comment by Joy — February 23, 2008 @ 5:28 pm
February 23rd, 2008 at 5:31 pm
Hi Oleg,
Good to hear.
Then I am assuming there isn't any problem with explaining the results of the Delayed Choice Quantum Erasure experiment.
The quantum effects are interconnected (i.e. entangled) in both space and time.
Penrose's Twistor Theory explains that Light Rays are points in Twistor Space.
The interconnected light rays of the referenced experiment are the same point in Twistor space.
Penrose explains the rules of the four dimensional Twistor Space is…
Z(0)*(~Z)(2) + Z(1)*(~Z)(3) + Z(2)*(~Z)(0) + Z(3)*(~Z)(1) = 0
Where Z(0), Z(1), Z(2) and Z(3) are the four complex dimensions and ~Z(0), ~Z(1), ~Z(2) and ~Z(3) are the complex conjugates of them.
If I am understanding correctly, this forces the "Regularization of Divergences" and prevents the same particle from showing up at two locations or to exhibit both wave-like and particle like behavior at the same time.
Is this "standard QM" too?
Comment by Thought Provoker — February 23, 2008 @ 5:31 pm
February 23rd, 2008 at 5:48 pm
Joy,
I have no idea what you're talking about. What are supercrystals? Whoever makes them to a precision of 0.01 angstrom? And most importantly, what do they have to do with virtual particles?
And the question "Where was the 'worldline' before it became 'real' (space? time? spacetime?) and what does it include?" is no more meaningful then "Where was the sound before I clapped my hands?"
All the best,
OT
Comment by olegt — February 23, 2008 @ 5:48 pm
February 23rd, 2008 at 6:18 pm
TP,
I am afraid the expression "regularization of divergences" has nothing to do with quantum entanglement and everything to do with technical problems in the quantum field theory. It treats particles as point-like objects, which often creates problems (like an infinitely strong electric field in the vicinity of a point charge). We know that a QFT description must break down on very short length scales (like Planck's length) but are not particularly worried about that: long-distance physics is insensitive to the detailed structure at short distances. So instead of building the correct theory of physics at the Planck scale we can regularize QFT by various mathematical tricks from non-integer dimensions to the introduction of a lattice, so that nonsensical infinite answers don't even show up. I am not sure of the details, but it's possible that twistors offer yet another way to do that.
The workshop you mentioned was dedicated to applications of twistors in string theory.
Comment by olegt — February 23, 2008 @ 6:18 pm
February 23rd, 2008 at 6:27 pm
< sigh > Thanks, Oleg. The thread's cumbersome anyway (approaching dial-up limitations). I'll just hang here on the sidelines throwing occasional asides like a good clown should, then. I know you won't mind… §;o)
Comment by Joy — February 23, 2008 @ 6:27 pm
February 23rd, 2008 at 7:05 pm
Hi Oleg,
The title of Penrose's first slide had in big letters…
Non-locality in the Wavefunction of a Single Particle.
I don't care what terms you use, it is obvious Penrose felt his talk had something to do with why a single particle could not be detected in two places (for example, going through two slits).
You might have gotten away with suggesting this wasn't the focus of this talk (maybe).
However, I suggest it looks like you are getting too wrapped up in the terminology and details. Like the proverbial fighting off alligators during a mission to drain a swamp.
I'm not interested in arguing the semantics, since I think Penrose was making his ideas clear enough.
Meanwhile, you still haven't offered a counter explanation for the Delayed Choice Quantum Erasure experiment.
Comment by Thought Provoker — February 23, 2008 @ 7:05 pm
February 23rd, 2008 at 7:07 pm
Hi Joy,
Thanks for trying. As always, please feel free to comment either up or down on how you feel I am doing in my representation of Penrose's ideas.
Comment by Thought Provoker — February 23, 2008 @ 7:07 pm
February 23rd, 2008 at 7:35 pm
TP,
Exactly. The focus of his talk is in Slide 5, Twistor—Strings. I have no idea why non-locality shows up on the first slide. I'll look up another talk of his at Kavli Institute in Santa Barbara.
Counter to what? I haven't yet seen what Penrose has to say on the subject.
Comment by olegt — February 23, 2008 @ 7:35 pm
February 23rd, 2008 at 8:10 pm
Hi Oleg,
Like I said, I will be patient while you look into Penrose's ideas.
I would appreciate if you let me know if and what you find in other slides.
Thanks again for pointing out the Twistor Theory/String Theory link.
Comment by Thought Provoker — February 23, 2008 @ 8:10 pm
February 23rd, 2008 at 8:18 pm
TP:
Oh, heavens, TP. I'll correct any misses I see, but don't count on me to see 'em. You're up on details more than I. I haven't read Penrose's tome – it's on my wish list for someday, if there's nothing else I need.
I had to play catch-up when I took the course, got and read all the requisite material (it had literally been decades since I'd run away with the circus on purpose). Asked maddening questions too. All I really wanted to know was if they were any closer to an answer to MY questions than they were when I'd left. They weren't, and still aren't, so thank goodness I hadn't wasted my life.
I'd love for Penrose's ideas to get the historical footnote as having opened the 'next door'. But it's still just a door, it's not a description of what's on the other side. Even Max [Planck] thought his 'constant' was a cheat. A lot of that going on.
Matti (like everybody else, it seems) is so hung up on his own formulae that he's accounting for anything and everything. Makes it fairly useless, IMO. Still, the p-adics might lead somewhere fruitful eventually. You never know.
I am too testosterone challenged to play this game. But I'll root from the sidelines as long as I can.
Comment by Joy — February 23, 2008 @ 8:18 pm
February 23rd, 2008 at 9:11 pm
Science and the Mind
Roger Penrose, Oxford University
Public lecture at the Kavli Institute for Theoretical Physics
University of California, Santa Barbara
The link contains an audio and slides. I have not listened to the entire lecture (it's 1-hour long), but it is much more accessible than The Road to Reality.
Comment by olegt — February 23, 2008 @ 9:11 pm
February 23rd, 2008 at 10:03 pm
Hi Oleg,
Yes, I liked that one (I have seen it before).
It gives a quick overview of Penrose's ideas from his philosophical view of the Platonic world to Orch OR model of consciousness.
However, it doesn't go into details about Twistor Space.
What did you think about the chess problem (quickly solvable by humans, difficult for Strong AI)?
Comment by Thought Provoker — February 23, 2008 @ 10:03 pm
February 24th, 2008 at 5:37 am
Hi Olegt,
Thank you very very much for the detailed responses and pointing me in the right direction as I was in error.
Being an EE/Math undergrad, my exposure to E&M was limited, and the APL course work is oriented specifically for engineers wishing to have a more in-depth understanding of physics. I look forward to my upcoming E&M course.
Thank you again.
regards,
Salvador
Comment by Salvador T. Cordova — February 24, 2008 @ 5:37 am
February 25th, 2008 at 2:06 pm
Hi TP,
I read your manifesto on another thread, here are some comments.
This proposition is in contradiction with experiments in quantum physics. There is such a thing as true randomness. Here is a quote from a recent essay in Nature The message of the quantum by Anton Zeilnger:
"Retrocausality" contradicts the well-established principle of causality, which still applies in relativistic physics, quantum mechanics, and the product of their marriage, relativistic QFT.
No, they are not complex. Quantum weirdness can be observed with the simplest quantum objects whose a "phase space" consists of just two states. The spin of an electron is a well-known example (it can only have projections +1/2 or −1/2 on any direction in space). Yet it behaves in the same weird manner as particles turning into waves. See Stern-Gerlach experiment.
The rest, as far as I understand, is a philosophical outlook, to which everyone is entitled.
Comment by olegt — February 25, 2008 @ 2:06 pm
February 25th, 2008 at 7:28 pm
Olegt:
How has this been verified? I looked up Zeilinger's essay, but it doesn't give much of a clue. Especially this statement by Zeilinger strikes me as rather overconfident:
How can you prove a negative like that?
Comment by Raevmo — February 25, 2008 @ 7:28 pm
February 25th, 2008 at 11:31 pm
Raevmo,
Though Zeilinger waxes poetic in the essay, he does not stray far from truth. It is well established that quantum randomness is not caused by a lack of information about the system (as happens with a chaotic classical system).
Physicists have thought pretty hard about the existence of hidden variables that could control the outcome of a quantum measurement, much like tiny deviations in a chaotic classical system determine its destiny. Without even knowing the exact nature of these hidden variables (but with a few technical assumptions such as their local character), physicists have deduced some very general results known as Bell's theorem. If quantum measurements appear random to us simply because we do not know the values of these hidden variables, experimental measurements should obey certain inequalities.
Experimental tests show that these inequalities are reliably violated. Thus the theory of hidden variables is overturned (at least in its local form), which means that quantum randomness is different from throwing a dice. We can know everything there is to know about the system and yet a subsequent measurement will give a truly random result.
You've probably noticed a caveat in the form of the technical requirement (locality of hidden variables). Loopholes exist, but they are being closed through further experiments.
In any event, this wild randomness is intrinsic to quantum theory. It arises from the non-commutative nature of operators (matrices) corresponding to physical observables. Operators of coorindate and momentum do not commute and thus one cannot know simultaneously the coordinate and momentum of an electron. Likewise, different components of electron spin do not commute and cannot be measured simultaneously. Even though we may prepare an electron in a state with its spin definitely pointing up (+1/2 along, say, axis z), its projection on a perpendicular axis (say, x) is completely undetermined and will be measured as +1/2 or −1/2 with equal probabilities. That is the weirdest thing about quantum mechanics.
All this other stuff (EPR and delayed quantum eraser) are just slightly more contorted versions of the plain-vanilla quantum weirdness. When you boil it down to an electron spin, no amount of special relativity is going to save the day. That's why I find TP's efforts so misguided. It just won't work.
Comment by olegt — February 25, 2008 @ 11:31 pm
February 26th, 2008 at 12:28 am
Hi Oleg,
That was a very nice presentation.
Agreed, quantum effects are non-local, non-algorithmic and, therefore, non-deterministic.
But does that mean they are random?
We know some quantum effects are definitely not random as demonstrated with GHZ states.
Wouldn't the more modest presumption be that quantum effects are not random even if we agree that they aren't the result of local hidden variables?
Comment by Thought Provoker — February 26, 2008 @ 12:28 am
February 26th, 2008 at 12:31 am
You know, the fields have become so specialized – so non-overlapping – that often those in one sub-sub specialty don't know much about what's real and current in other sub-sub specialties.
Takes sort of a "Renaissance Man" (or WOman) to connect dots in times of theoretical turmoil. Those who demand pre-connected dots have no talent or imagination, or know nothing about the issues in the sub-sub fields that need rectifying.
…and those who presume that what's public knowledge (press release and all) in sub-sub fields they barely keep up with are All The News That's Fit To Print are hopelessly naive. Really.
Comment by Joy — February 26, 2008 @ 12:31 am
February 26th, 2008 at 9:42 am
Thanks for the compliment, TP.
I don't think we have reached a point of agreement. Quantum effects appear nonlocal only if one tries to interpret them in terms of classical physics. However, these kinds of analogy are fraught with peril, as violations of Bell's inequalities demonstrate. It seems more appropriate to ditch the classical analogies altogether and boldly follow the postulates of quantum theory. All roads lead to Copenhagen.
Besides, non-locality isn't going to help you. An electron is as point-like an object as can be: it has no internal structure as far as we know, except possibly on the Planck scale (for which you need string theory and that's again quantum mechanics). Yet even this basic building block of matter, whose entire phase space consists of two states (spin up or spin down), exhibits quantum weirdness. Prepare an electron in the state with its spin up (+1/2 along z), then try to measure the spin component along x. It won't be 0 because it must be +1/2 or −1/2. And you will find it to be +1/2 or −1/2 with equal probabilities and totally random. If there is a perfect generator of random numbers, this is it.
Not sure what you mean by non-algorithmic, maybe you should spell it out. Let me stress again that quantum randomness is intrinsically different from its classical counterpart. Classical dynamics is inherently deterministic. Laplace famously said that, given velocities and coordinates of every particle in the world, he could predict the future of the universe. That is, of course, impossible: small uncertainties in the initial velocities and coordinates grow exponentially (that's the technical definition of chaos) turning the deterministic evolution of the system into a stochastic one (and that's the basis for statistical mechanics).
Quantum mechanics, in contrast, contains uncertainties even when we have complete knowledge about the system (zero entropy). Knowing the z component of an electron spin means that the x component is undetermined. Not just unknown, but completely unknowable. And vice versa. This is the bare-bones version of the particle-wave dualism. If we prepared an electron in a state with a definite momentum (that's an infinite sine wave), its coordinate is unknowable, and vice versa. We can compromise and make both the coordinate and momentum somewhat well-determined, as in wave packet. The product of their uncertainties is guaranteed to be at least h-bar.
Modesty is not a virtue when it comes to physical theories. Inherent randomness is a bold prediction of quantum theory that can—and has been—tested. Statistical tests of a random bit generator based on atomic decays are described here. Take a look.
If it looks like a duck, walks like a duck, and quacks like a duck, perhaps it is a duck.
Comment by olegt — February 26, 2008 @ 9:42 am
February 26th, 2008 at 11:41 am
Oleg said to TP:
There is this beastie in the stable of fundamentals that we call "human." They are tiny and all look exactly alike (to Ubersci-guys). Prepare a human (any one from among the billions that infest this pebble) in state 'live' and then try to measure state 'sex'. You will find it to be M or F with equal probabilities and therefore totally random.
Knowing the E [existential] component of a human means the S [sex] component is undetermined. Not just an unknown, but completely unknowable. This must mean humans are not male or female until the great galactic Ubersci-guys decide to find out. And when they decide to find out, it's a completely random 50-50 disposition. A perfect random bit generator!
Comment by Joy — February 26, 2008 @ 11:41 am
February 26th, 2008 at 12:02 pm
Hi Oleg,
I was tempted to be quiet and let others have a chance. However, I decided to point out a couple of things. First, it is interesting that you used the "Looks like a Duck", because Mike Gene suggests the ID argument is a "Duck" verses "Rabbit" argument over something that looks like both a rabbit and a duck.
A good psuedorandom number looks like a duck.
PI can be calculated in binary. Does that mean the bit-by-bit choice is random?
These examples are both known to be algorithmic, so most people don't think of them as random (looks like a rabbit).
It you want to say quantum effects exhibit a "random distribution" as proof it is random, then the two above examples look like both a duck and a rabbit.
Comment by Thought Provoker — February 26, 2008 @ 12:02 pm
February 26th, 2008 at 12:44 pm
Joy:
The analogy with electron spins is not perfect. It's been known for a while that (a) sex compositions of human families do not follow the expected binomial distribution (observed distributions have greater variance), and (b) M and F do not have equal probabilities.
Therefore, we finally have solid scientific evidence that humans are not electrons. Well, most humans anyway.
Comment by Raevmo — February 26, 2008 @ 12:44 pm
February 26th, 2008 at 10:27 pm
Raevmo,
Joy's "example" misses a much more important point. A human can be alive and have a definite gender at the same time. With an electron's spin it's different: you can specify exactly the x component of a spin or the z component, but not both. Even if a spin was prepared with a well-determined z component (say, +1/2), it will becomes completely undetermined once we have measured the x component.
Comment by olegt — February 26, 2008 @ 10:27 pm
February 26th, 2008 at 10:53 pm
TP,
That is only part of the proof. Experimentally observed violations of Bell's inequalities demonstrate that quantum randomness is nondeterministic, unlike its classical counterpart (or the digits of π).
I want to stress once again that quantum uncertainty does not reflect a lack of knowledge. In the above example with spin measurements we have a maximum amount of knowledge possible, which is reflected in zero entropy of a pure quantum state. The entropy goes up by log2 after the measurement, when the pure state becomes mixed. The change in the entropy is ultimately caused by the impossibility to simultaneously answer the questions (a) does the spin point along +z? and (b) does the spin point along +x? A positive (or negative) answer to one of these makes it impossible to answer the other. That is the essence of quantum weirdness and it shows up in many other situations, including the particle-wave duality.
Comment by olegt — February 26, 2008 @ 10:53 pm
February 26th, 2008 at 11:25 pm
Raevmo:
But humans *are* electrons. Mostly, anyway. Just like everything else.
Oleg said:
To which Joy replies, So What? WE know humans can have both attributes, Galactic Ubersci-guy does not. And never will know so long as the a priori assumption he starts with is that it's completely random on the secondary attribute end. If Ubersci-guy's test for sex kills the subject, he's never going to have a live human with a definite sex – it is impossible to have both at the same time. Killing the subject totally messes with the "live" parameter.
…I still think it would be a gas if it turned out there's only one electron, and the Ubersci-guys from our level just keep on measuring this attribute or that attribute over and over and over again, and it gives them different answers every time. Worse than quicksilver, the darned things are!
Comment by Joy — February 26, 2008 @ 11:25 pm
February 26th, 2008 at 11:53 pm
You got it backwards, Joy. We didn't assume that a spin cannot have two definite components at once. To the contrary, the assumption was that it can. However, the Stern-Gerlach experiment with electrons indicated otherwise. Now we know for sure that it's not our ignorance at fault (as you seem to suggest), but rather that it is an intrinsic property of quantum mechanics, which, incidentally, is related to the noncommutativity of rotations in three dimensions.
Comment by olegt — February 26, 2008 @ 11:53 pm
February 27th, 2008 at 12:14 am
< sigh > It was a joke, Oleg. Sort of like "How can you be in two places at once if you're not anywhere at all?" [Firesign].
Tell me something… do you take yourself as seriously as you appear to take us IDers?
Comment by Joy — February 27, 2008 @ 12:14 am
February 27th, 2008 at 12:20 am
Joy, I won't take you seriously from now on. Promise.
Comment by olegt — February 27, 2008 @ 12:20 am
February 27th, 2008 at 8:42 am
You didn't take me seriously in the first place or you wouldn't have engaged this tack. …and you would have grokked the aside.
Comment by Joy — February 27, 2008 @ 8:42 am
February 27th, 2008 at 12:41 pm
The definition of "random" in QM suggest the inability, given identical boundary conditions, to get identical outcomes in some measurements.
We can get similar probability distributions given the same boundary conditions, but we cannot get the same outcome. For example in a double slit experiment, using a single photon detector, the detected position of each emission will be different each time even though we've not changed the position of the emitter or the double slit.
The question of the Bell inequality is to determine whether our intuitive notions of "random" exist in QM, and indeed they do.
Regarding an underlying mathematical edifice, a possible analogy in mathematics is the existence of non-computable numbers, these numbers have no deterministic, no algorithmic description, yet they exist. In fact, there are more non-computable numbers than computable numbers (pi, square root of two, are computable….non-computable are beyond description)….
Physicist Paul Davies suggests there is "free will" in math because of non-computable numbers and incompleteness in math, thus it should not be surprising there are pockets of non-determinism in physics.
What olegt has said is standard physics. My professor of QM at GMU, Trefil, was Bell's colleague.
Comment by Salvador T. Cordova — February 27, 2008 @ 12:41 pm
February 27th, 2008 at 7:02 pm
Regarding an underlying mathematical edifice, a possible analogy in mathematics is the existence of non-computable numbers, these numbers have no deterministic, no algorithmic description, yet they exist.
Numbers don't exist at all, they are conventions in a formal system we use to categorize the world. This describability of some object in this formal system is no guarantee that any comparible thing exists.
In fact, to my limited understanding, even the basic dimensions of length and time are quantized, so uncountable numbers *can't* exist.
Physicist Paul Davies suggests there is "free will" in math because of non-computable numbers and incompleteness in math, thus it should not be surprising there are pockets of non-determinism in physics.
What? We know there are uncomputable numbers because where A=#(N), (N = {1, 2, 3, … }), there are only A computable numbers and 2^A real numbers in our formal system. Incompleteness is based on a similar, if more complex, notion that you can't reach every statement with countable means. How you get free will out of that is mind-boggling.
Comment by One Brow — February 27, 2008 @ 7:02 pm
February 27th, 2008 at 8:16 pm
The guys in the Quantum Computing Lab are going to be sorry to hear that QM is "non-algorithmic" or "non-computable."
For that matter so are all quantum physicists who thought they were actually computing quantum physics!
(And quantum physics ain't "weird." Anymore so than anything else!)
Comment by Rock — February 27, 2008 @ 8:16 pm
February 27th, 2008 at 11:26 pm
Rock,
I fully agree with you on quantum physics being algorithmic and computable.
That said, mystery, like beauty, is in the eye of the beholder. As physical theories go, quantum mechanics is probably the weirdest of them all in my view.
And I am not alone. Roger Penrose wrote in The Road to Reality:
Note that I am not equating weird with incomprehensible. I am simply expressing my astonishment at the wonders of Nature.
Comment by olegt — February 27, 2008 @ 11:26 pm
February 28th, 2008 at 12:11 am
TP,
I have finally got the book.
Having looked at it, I must say that this book is not meant for a lay person. While it is not impossible to start from scratch and learn on the fly, the learning curve is so steep that you must be extremely sharp and have lots of time on your hands to accomplish that. Frank Wilczek, in his review of Penrose's book in Science, pointed out another, deeper problem:
This is a good book for those who have already been exposed to quantum mechanics at the level of a graduate course, maybe top-notch undergrads—people who have internalized how quantum mechanics works and would like to broaden their mathematical horizons and learn some recent ideas in mathematical physics. I'd be interested to know your impression of the book.
At any rate, I'll scan it for material relevant to the discussion on this thread and get back to you.
Comment by olegt — February 28, 2008 @ 12:11 am
February 28th, 2008 at 1:17 am
Hi Oleg,
Thanks
My impression of the book is that one could spend a great deal of time working out all the puzzles that Penrose sprinkled throughout the book (e.g. page 170 "Do this, by taking advantage of a power series expansion for log z taken about z = 1, given towards the end of [SECTION 7.4]".
It is obvious Penrose is very much the mathematician.
I like to think I am a quick learner, but this took me quite a while to even understand the basics or what Penrose is saying.
I hope to find the time to go through the book again and work out some of the problems. But I don't see it in the near future.
Yes, I agree, Penrose lays out a very detailed case. Which is why I am looking for counter arguments and other ways to look at it.
I thank you for your efforts and hope any headaches you get from reading Penrose's book aren't too severe.
Comment by Thought Provoker — February 28, 2008 @ 1:17 am
February 28th, 2008 at 2:54 pm
I think it is a mistake to assume that the existence of computers somehow negate the non-algorithmic nature of QM. Computers have to be designed such that the randomness of QM is limited and suppressed. For example:
here
When tunnelling will occur cannot be precisely predicted any more than the when a specific radioactive decay will occur. We can predict distributions, not specific outcomes.
Thus we can build computers because we have techniques (such as error correction) or architectures to limit the propagation of unwanted QM randomness and preserve the semblance of deterministic behavior in the computer.
Nano-molecular computers are even more vulnerable to noise from quantum processes, so it takes work to negate the fact QM is not always amenable to the computations we wish to carry out.
Penrose's book Emperor's New Mind dealth with non-algorithmic phenomenon, incompleteness, QM, and AI.
If we treat the universe as some massive computer with all the quantum systems as bits, then yes, we can say QM is algorthimic in that sense, but not in the sense that the algorithm is accessible to us.
One can say, because of Heisenberg uncertainty, the Computer that is the Universe will conspire to behave in a manner that appears capricious to us. So at least from an operational standpoint. the behavior of Quantum phenomena have an aspect of capriciousness and unpredictability, and thus in an operational sense, it is not algorithmic.
Algorithmic means we can describe it in deterministic detail: i.e. "given this condition, this outcome will happen". I don't think we can do that with QM, ever.
Comment by Salvador T. Cordova — February 28, 2008 @ 2:54 pm
February 28th, 2008 at 4:46 pm
QM has nevertheless inspired thinkers to believe that the universe is some kind of computer.
I think that scientists as Chaitin and Anton Zeilinger support this "digital philosophy"
The following website gives an introduction for the layperson
http://www.bottomlayer.com
http://www.bottomlayer.com/bot...
Best
Albert
Comment by Voie — February 28, 2008 @ 4:46 pm
March 2nd, 2008 at 7:17 pm
TP,
I have browsed through The Road to Reality and read a few sections more closely. I like the book. It has lots of useful mathematical tricks and I'm sure that some of them will end up in a QM class that I'll teach one day.
Penrose gives a nice exposition of the paradoxical aspects of quantum measurement, including quantum entanglement. However, I have found no indication that he attempts to reduce quantum weirdness to the geometry of spacetime. I may have missed something but from what I read I consider that unlikely.
Same with twistors. Penrose views them as a mathematical device that on its own will not solve the problem of quantum measurement but may be helpful one day when we have an insight from experimental physics that requires new mathematics and twistors are it. On p. 1004 he writes:
Once again, twistors and Minkowski space are mathematical concepts that have no physical meaning on their own. Physics is more than just math. That is why I was skeptical of your assertions from the beginning. Reading Penrose only confirmed that.
If you have any further questions, I'll be glad to answer them.
Comment by olegt — March 2, 2008 @ 7:17 pm
April 5th, 2008 at 3:14 pm
Hi Olegt,
I am glad you read the book, even more so since you liked it. I presume you are trying to be respectful by suggesting that when Penrose concedes Twistor Theory is a MATHEMATICAL model, you take it to somehow mean Penrose is being scientifically humble and isn't actually presenting it as being correct.
Penrose's Black Hole model was purely mathematical. By the time physical evidence was found Penrose, and others, presumed Black Holes existed. The model was too complete and made too much sense to be wrong.
I suggest Penrose didn't need physical confirmation of Black Holes to believe in them.
Likewise, String Theory is purely mathematical. It is clear Penrose treats his Twistor Theory to be on equal, or better, footing than String Theory. Here is what Penrose Said on page 1004 following the quote you gave…
"…the primary case for Twistor theory indeed lies, like string theory (or M-theory) in the strength of its aesthetic or mathematical appeal. The two theories are, however, mathematically incompatible as they stand, because they operate with different numbers of spacetime dimensions."
You also wrote…
Now, it may be my lack of understanding, but it seems to me that String Theory and Twistor Theory are primarily about explaining the foundation of quantum physics. That would include making sense of "quantum weirdness".
Furthermore, it seems to me that Twistor Theory directly deals with "the geometry of spacetime".
Therefore, I am puzzled that you "found no indication" of a connection when I think it was one of Penrose's main purposes of The Road to Reality to provide the foundation for the quantum/geometry connection by starting with basic geometry principles, explaining "basic" Minkowskian Geometry and, finally, presenting his Twistor Theory as a geometric model for establishing "an important thread of connection"¦between the physics of the large and the physics of the small." page 962
You wrote…
Thank you. Here are some questions"¦
Do you consider String Theory to be part of Physics ("more than just math")?
What is your reaction to Penrose saying…
"ds^2 = dt^2 – dx^2 – dy^2 – dz^2
is more directly physical…the integral ds (with ds>0) being directly interpretable as the action physical time…" on page 413 in the chapter titled Minkowskian geometry? (Is it "more than just math"?)
One of the reasons I have focused on the light code (null geodesic) in past discussions was from Prenrose statements like… "As far as I can make out, quanglement links are always constrained be the light cones, just as are ordinary information links, but quanglement links have the novel feature that they can zig-zag backwards and forwards in time, so as to achieve an effective 'spacelike propagation'." page 603.
I see this as a precursor to the Twistor Theory's geometry where "A light ray in Minkowski spacetime is represented as a single point in the twistor space." page 964
Whether or not you agree with this aspect of Penrose's thoughts, do you see why I feel Penrose directly ties relativistic spacetime geometry to his explanation of quantum physics?
Comment by Thought Provoker — April 5, 2008 @ 3:14 pm
April 5th, 2008 at 7:33 pm
TP,
String theory applies principles of quantum mechanics to dynamics of extended one-dimensional objects, strings, much like quantum field theory deals with zero-dimensional objects, particles. Neither of these theories sets out to "make sense" of quantum physics. They take it as a starting point.
Yes, the mathematics of twistors is well suited to dealing with null geodesics. That said, null geodesics are mathematical objects introduced in the framework of the purely classical (i.e. non-quantum) theory of relativity. Null geodesics in themselves have nothing to do with quantum phenomena, much like straight lines in Euclidian space aren't wedded to waves.
In that passage Penrose says: look, twistor algebra is natural for spacetime. Both twistor algebra and quantum mechanics of quantum spins involve complex numbers. Ergo, twistors are somehow connected to quantum spins. However, it's a tenuous relation, which may or may not have important consequences.
Penrose writes further down (p. 966-967): "this provides us with hints as to Nature's actual scheme of things, which must ultimately unify spacetime structure with the procedures of quantum mechanics." From this quote it is clear that Penrose does not have a clear idea about the nature of the purported link between quantum mechanics and spacetime. Vague mathematical similarities usually can't replace physical principles. Recall, for instance, that the description of ac circuits also involves complex numbers. Are these circuits relevant in any way to quantum mechanics? The math can be used in many contexts, but it does not establish a physical similarity.
No, not yet. A theory must go through experimental testing before it can be accepted as a physical model describing reality. That hasn't happened yet to string theory.
In relativity, the interval gives proper time. Theory of relativity has been thoroughly tested by experiments, so it is more than just math, it is a physical model that describes our world.
I think he makes it more complicated than necessary. Even without entangled pairs, quantum mechanics demonstrates non-local correlations at the level of a single particle. For instance, if you measure the position of an electron that passed through a slit (or two), there is a finite-size spot where it can be detected, so it is described by a wavefunction that is extended in space. However, once your detector determines the location of the electron, its wavefunction instantaneously shrinks to that single spot and you immediately know that it will not be found at any other location. All these points in spacetime are spatially separated, as in the passage you quoted. What zigzags forward and backward in time in this case? I don't see any reason to think that a purely geometrical "explanation" stands behind all of quantum physics.
Sure I do. Penrose leaves lots of clues that maybe, just maybe, there is some deep connection between geometry and quantum physics. At this point, however, he has no clear idea what the nature of that connection might be.
Still, if I understand his speculations correctly, he is leaning in the direction opposite to yours. His spin networks are an attempt to generate geometry out of quantum physics. You, on the other hand, suggest that it is quantum mechanics that emerges from geometry.
Best,
Oleg
Comment by olegt — April 5, 2008 @ 7:33 pm
April 5th, 2008 at 10:51 pm
Hi Oleg,
I really appreciate the time and effort you took in helping me with this. When I asked "…do you see why I feel Penrose directly ties relativistic spacetime geometry to his explanation of quantum physics?"
You answered…
These little words mean a lot coming from someone of your background. I helps confirm I am not totally clueless (at least on this subject).
It doesn't even bother me that you added…
I could only hope my biggest confusion is understanding cause/effect relationships in concepts from which time, itself, emerges.
I never expected to avoid chicken/egg paradoxes. On the contrary, I felt they were a given.
I doubt that I could do better than Penrose at convincing you of the soundness of his logic. However, there is at least one thing I would like to point out to you. You wrote…
If I understand you correctly, this is the aspect of Twistor Theory that Penrose appear to be most proud of. "Quantum phenomena" EMERGES from mathematics that should have nothing to do with it. I was going to try to quote Penrose directly, but that would have required too much typing so please read starting at the beginning of section 33.7 on page 982 and then note the section ends with Penrose illustrating the "chiral nature of twistor theory". IOW, Twistor Space takes on a lop-sided aspect for right and left handedness. In section 33.8, Penrose brings in "Massless fields of mixed helicity-such as a plane-polarized photon, which is the sum of a right-handed and left-handed part". The result of this strikes Penrose "as being somewhat magical." (can't you just feel how much Penrose loves and believes in his math?). Section 33.9 is six pages of Penrose trying to explain "sheaf cohomology" whose ideas "…are fairly sophisticated mathematically, but actually very natural." Penrose uses this to introduce non-locality to the chain of discussion (I freely admit that my attempts to understand it mostly result in only making my head hurt). Section 33.10 explains how positive/negative frequency splitting along with "holomorphic first sheaf cohomology" plays "a direct role in generating deformations of twistor space." This leads to section 33.11 titled, The non-linear graviton. Here, Penrose's quantum gravity falls out of this Twistor Model.
As you know Penrose, and others, have proposed experiments to test the E=h/t of quantum gravity. If this is shown to be correct, I think it would portend for some very interesting discussions, including those involving the Penrose/Hameroff Orch OR model.
But, for the moment, the twistor theory is not a full-blown physical theory (Penrose admits this on page 1001). However, I am biasedly encouraged by the recent developments you have pointed out on a Twistor-string Theory that have occurred since The Road to Reality was written.
I was going to try to do a summary of all of our discussions, but this comment took to long. Maybe some other time.
Thanks again,
TP
Comment by Thought Provoker — April 5, 2008 @ 10:51 pm
April 6th, 2008 at 9:58 am
TP,
Let's dwell a bit on Ch. 33.7, Twistor quantum theory. At the beginning of it, Penrose writes:
Note that Penrose's program is to unify quantum mechanics and spacetime structure, rather than to derive the former from the latter.
A physicist might guess from that brief passage that the program is to be realized in the standard way, through canonical quantization. First, obtain a classical description of the physical system. Twistor math introduced in previous chapters is precisely that, a classical theory dealing with classical trajectories of massless particles. Next, identify pairs of canonical conjugate variables, such as coordinates and momenta for pointlike particles (Ch. 21.2), the angular variables φ and cosθ for spins, or whatever. Finally, quantize the theory by promoting one variable in the canonical pair to a differential operator. See p. 496, where this procedure is implemented for the case of a nonrelativistic pointlike particle.
Back to Ch. 33.7 (p. 983), where Penrose implements canonical quantization for twistors. He identifies Z and Z-bar as a canonical pair and then promotes Z-bar to a differential operator hbar d/d Z-bar. At that point, twistor theory is quantized. Subsequent chapters deal with the consequences of this quantization.
It is now crystal clear that, contrary to your suggestion, Penrose does not derive quantum mechanics from his twistor description of spacetime. Instead, he applies the standard quantization procedure to twistor theory, the same canonical quantization that has been previously applied to nonrelativistic particles, spin, Maxwell's electromagnetic field and strings. Quantumness does not arise from spacetime, it is applied to spacetime parametrized by twistors.
Does this help?
Comment by olegt — April 6, 2008 @ 9:58 am
April 6th, 2008 at 3:33 pm
Hi Oleg,
You wrote…
Thank you for providing the contrary position. On page 962 Penrose was comparing his twistor theories to the alternatives…
"All these ideas concentrate on the construction of notions of 'spacetime' that take on aspects of discreteness of 'quantum' characteristics of some kind. In the remainder of this chapter I shall describe a quite different family of ideas, namely those of twistor theory (to which I have, myself, now devoted over 40 years!) in which there is no discreteness specifically imposed upon spacetime…it does not directly lead to any notion of a 'discrete spacetime'"
I had read this a Penrose identifying something unique about his theory (pride?). I am now rereading this to understand even if discreteness ('quantum') wasn't imposed upon spacetime, that doesn't mean Penrose didn't impose discreteness on his definition of twistor space to allow for quantum phenomena.
I don't have enough mathematical background to judge the degree Penrose artificially force-fit this into his theory. I get the impression that has been a large part of the reason why Penrose's twistor theory has lacked acceptance. Even though no one has managed to poke significant holes in the logic, few can understand it as well as Penrose does. Apparently, Witten was one of the unique few. From the link you provided on the subject…
The emerging link between twistors and string theory arises from the complex-space nature of twistor space. In modern string theory, the space representing the six hidden dimensions is a space of three complex dimensions known as a Calabi-Yau space. The strings themselves are usually taken as lying inside the Calabi-Yau spaces, but these spaces are artificially imposed. In twistor theory, we can put the strings into twistor space instead. The geometrical correspondence between twistor space and the four-real-dimensional space-time of special relativity means that twistor space now does double duty: it simultaneously supplies the needs of both the Calabi-Yau spaces and space-time itself. Accordingly, the strings now become complex curves — Riemann surfaces, to be specific — in twistor space!
The development of these ideas is due mostly to Edward Witten of the Institute for Advanced Study in Princeton, New Jersey, who has been the main driving force behind new directions in string theory since the late 1980s. It seems to me that there are some striking developments coming from this new approach, and it will be exciting to see how far these ideas can be extended towards a comprehensive physical theory with something serious to say about quantum gravity.
Twistor theory has been around for a little over four decades now. Like string theory, it has had more impact on pure mathematics than on clear-cut physical results, but as the string theorists begin to take it up it may just be coming into its own as a physical theory. And, since fully fledged twistor theory calls for just three space dimensions and one time dimension, the first result of this emerging union may well be that those extra dimensions of string theory slip quietly away.
While I wish I could understand it better, it sure sounds promising.
You asked…
Very much so. I want a realistic picture. I expected and accept that it is possible that most of this is Penrose manipulating the math to look good. It wouldn't be too hard to fool me. But I suggest that manipulating math to complete a model is better than trying to impose extra, undetectable dimensions.
If Witten et al can paint a complete model that corresponds to observations and is testable, that would go a long way for establishing the twistor-string theory as a physical theory, IMO.
Let me see if I can summarize things for our listening audience…
In the 1994 debate between Hawking and Penrose, the two of them agreed more than they disagreed. The major disagreement between the two boiled down to the treatment of mathematical models. Penrose tended to argue that models should be developed to explain everything (including Schrödinger's cat Gedankenexperiment) in order to understand reality. Hawkings rejected the notion of pursuing reality because observations is all we have to work with ("Reality is not a quality you can test with litmus paper.") In this vein, it appears that Hawking considers any model that matches observations to be good enough. Oleg, you come across as having more in common with Hawking in this regard (although you seem to embrace Copenhagen stronger than Hawking).
To me, when I see the completeness and beauty of Minkowskian geometry, the math becomes something I can embrace. I don't consider it Truth because I know it could be wrong, but it still seems more than just math that happens to match observations. Especially when I can use it to derive curved Schwarzschild geometry.
This is the point I was trying to get across with my argument against Special Relativity and saying the twin paradox is a geometry problem (twin takes a short cut). Of course the math of Special Relativity matches observations in the SPECIAL case when you pick the correct reference frame and make other assumptions. Like Penrose did in his debate, I point at it and say something is wrong with math that is that incomplete and artificial. The Hawking response is that it isn't wrong as long as it matches observations for the cases in which it is used. But this doesn't make sense to use it when the geometric solution is more complete and more universal.
Penrose's twistor space is a geometric model that is rather complete. It encompasses the spacetime geometry and makes significant inroads in making "an important thread of connection"¦between the physics of the large and the physics of the small."
Oleg, if I understand correctly, you and I have very little disagreement when it comes to the physics of the large. Our potentially biggest problem is that when the math indicates the path-length of a light ray is ZERO, I embrace that as reality. To me, I accept that our observable universe is actually the complex geometry described by Minkowski, Penrose and others. I consider it more than just math. Penrose's twistor space directly deals with zero path-lengths by representing light rays as single points.
I presume the physics of the large must somehow be the same as the physics of the small. Reality is reality.
With this is mind, to me spacetime geometry provides basic explanations for quantum experiments like Delayed Choice Quantum Eraser. It is a geometry problem with light rays being points.
Oleg, having read Penrose's book, would you agree that Penrose's twistor theory provides a basic explaination for this experiment (especially since is was done with light and not heavier particles)?
If we presume the twistor-string theory gains acceptence, it will result in something I have pointed out multiple times. It is ironic that it looks like it is easier to solve the riddle of combining the physics of the cosmos with quantum physics than it is to explain our everyday world.
IOW, it is our everyday world that is "weird" not Quantum Mechanics.
This is why I think Penrose has already presumed his twistor theory and quantum gravity are correct (even if he is missing some of the details). He has already moved on to the followup problem, providing a complete model for decoherence. And, no decoherence model would be complete without explaining the Schrödinger's cat Gedankenexperiment.
Ergo, Penrose had to explore the role of consciousness which resulted in him writing several books and embracing Hameroff's ideas for Orch OR.
Whether or not Penrose is on the right track, I think I understand what he is doing and why.
Comment by Thought Provoker — April 6, 2008 @ 3:33 pm
April 6th, 2008 at 4:57 pm
TP,
I don't have major problems with anything before this paragraph in your last comment. There are some things that I would phrase differently, but they are minor points compared to what lies beyond the quoted paragraph.
Concerning this paragraph itself, I don't share your fascination with null geodesics, but that's okay: beauty is in the eye of the beholder. I actually agree that Minkowski geometry is more than just math: it is a physical model of our spacetime, tested and found accurate.
But let's go to the next couple of paragraphs.
Physics of the large is not necessarily the same as physics of the small. Properties of a crystalline solid (say, gold) are very different from those of a single gold atom. For instance, a crystal has rigidity, a single atom does not. I suspect that you may mean something else by that, like there should be a universal theory that describes everything from the Planck scale to the scale of the Universe. It's a pipe dream. Physics is a patchwork of theories applicable each in its own domain. Quantum mechanics is useful on the scale of a few angstrohms, but no one in his right mind applies it to the description of, say, airplane motion. It is neither practical, nor necessary. That said, different patches of physical theory overlap with one another and they must agree in the overlap region. Indeed, we know that equations of quantum mechanics reduce to classical physics when we deal with large objects (Schroedinger's cat notwithstanding). Relativistic dynamics turns into Newtonian at low velocities. And so on. At the moment, however, quantum physics does not patch up with general relativity, so this is an area of current research. Nonetheless, a theory that will eventually unify the two on the small scale will not be a theory of everything. It will be a theory useful in its realm of mind-bogglingly small distances and high particle energies. However, it won't supplant either quantum mechanics or general relativity outside of that realm.
This is your fantasy, TP. Penrose has never said anything that could be interpreted in this way. We have gone over his book over and over and there is nothing even resembling that. I completely disagree with this (mis)characterization.
What you pointed out multiple times falls into two categories: (a) things long ago accepted by physicists such as the shortcut in Minkowski space. (b) mischaracterizations of passages in Penrose's book, like Minkowski geometry somehow explaining quantum entanglement. (Sorry about being blunt, but since you are summarizing our dialog for the lurking reader, I have to call a spade a spade.) Penrose has never suggested that. I have just explained to you that twistors are quantized like everything else and that quantum physics is not a consequence of twistor math. Yet for some reason you still cling to this totally bogus claim. It's your right to say whatever you want, but it's also my right to point out that it is complete BS.
Whatever you say. Weirdness is a subjective characterization.
A careful reading of the book suggests that Penrose is much more modest in his assessment of twistor theory. In Ch. 33.14 The future of twistor theory? (p. 1003) he writes:
He goes on to list some known difficulties of twistor theory (like the left-right asymmetry). On the next page he writes:
I can summarize these passages in a shorter way: at this point, twistor theory is just math. I am quite certain that it is an accurate characterization, one with which even Penrose would agree.
Sadly, I must tell you that you don't understand what Penrose is doing and I am not sure that I can help you. I tried above to explain what Penrose did with twistors. However, there is certain prerequisite knowledge that one must possess in order to appreciate Penrose's book or my explanations in the previous posts. One needs, at the very least, to know quantum mechanics at the level of a two-semester undergraduate course: canonical quantization, operators, wave functions, that sort of things. I still don't know whether you have that knowledge. Perhaps you could describe your background.
Comment by olegt — April 6, 2008 @ 4:57 pm