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  Even if one (erroneously) believes on some (rationalistic) philosophical grounds that Bohm's theory is irredeemably flawed, it remains a fact that no local theory can account for the results of certain experiments.  That's what Bell proved.  Superluminal causation is a fact of nature.

Let me make sure I understand your terms. A "local theory" is one in which all causation can be shown to propagate at less than the speed of light. And you are saying that Bell has proved "superluminal causation" -- which I presume means causation that propagates faster than the speed of light. But, Bell does not claim to have proved "instantaneous causation", i.e. causation that propagates at an infinite speed. Is that correct?
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Let me make sure I understand your terms.  A  "local theory" is one in which all causation can be shown to propagate at less than the speed of light.  And you are saying that Bell has proved "superluminal causation" -- which I presume means causation that propagates faster than the speed of light.  But, Bell does not claim to have proved "instantaneous causation", i.e. causation that propagates at an infinite speed.  Is that correct?

That's right.

Maybe this will be clarifying, though. There's a slight imprecision in saying that "Bell proved superluminal causation". What Bell proved is that theories of type X will always predict that a certain correlation obeys a certain inequality. X here means that, according to the theory, the outcome on each side is determined by local variables: the settings of the detector and the state of the particles. (I assume you're aware that in the relevant experiment, pairs of particles are emitted from a central source, and then certain of their properties are measured by well-separated detectors.) Now, when they actually do the experiments, the inequality is violated. That means the "true theory" (whatever it is) is not of type X. It must involve some sort of dependence of one of the measurement outcomes on the distant apparatus/setting/particle/outcome -- something "nonlocal" to that particular measurement event. So that is the "action at a distance." That Bell's inequality is violated simply proves that there is some kind of action at a distance.

The specific claim that the action is superluminal comes, not from anything Bell proved, but from the experiments. The apparatus settings on the two sides are randomly flipped back and forth in such a way that the final setting -- the setting actually used in the measurement of the particle -- isn't even made until right before the particle gets there. And the timing and distance between the two wings is such that the "information" about the setting on one side would have to travel faster than c to make it to the distant side in time to affect the outcome there. (And we know it *does* affect the outcome there because the inequality is violated.) Does that make sense? So what the experiments give us is a lower-limit on the propagation speed involved. (Basically, it's the distance between the two detectors divided by the timescale of the setting swapping.) My point is just to stress that it's the experiments, not Bell's theoretical analysis, that tell us something about the speed. Bell's inequality is simply a criterion for whether or not something on one end is affecting something on the other end. The experiments tell us that this kind of effect is indeed present, and it's details of the experiment (namely, how "late" the relevant somethings on each side even come into existence, and how far away the distant something is at that time) that speak to the speed.

There are a number of different experiments which all imply somewhat different lower limits on this speed. And the various experiments are different in other relevant ways, too, e.g., efficiency: the fraction of emitted particle pairs which are actually detected in the relevant way. In principle, so long as some of the pairs are missed, one could have a kind of conspiracy theory view that the sample of actually detected pairs is biased (so that, if only those missing pairs had also been detected, Bell's inequality *wouldn't* have been violated). But I think we can leave all those "loopholes" aside and just say: the weight of the evidence to date *strongly* suggests that Bell's inequalities *are* violated and that the relevant causation (if it involves propagation of anything at all) involves propagation with a speed that is at least several times faster than the speed of light.

You may have heard elsewhere that "superluminal" and "instantaneous" are in some sense equivalent, so that it makes no sense to talk about signals which are superluminal-but-not-instantaneous. This is valid only if one assumes that relativity has got it right when it comes to the basic causal structure of the world. But what these experiments show is precisely that relativity *hasn't* got it right. If there is superluminal causation (and the experiments say there is) then relativity (which is supposed to prohibit this) is just wrong, and the relativity-motivated identification of "superluminal" and "instantaneous" is off the table. So nobody needs to worry that faster-than-light causality somehow entails "real infinities" or anything else that could be regarded as in conflict with metaphysical axioms.

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I recognize that many honest people may not be in a position to assess the technical evidence on this issue. 

[...]

I am not a physicist, so I can not address your points coherently. Stephen Speicher, on the FORUM for Ayn Rand Fans, is who you should be talking to. If you go to the website, send him a PM, and see if you can get in touch with Dr. Lewis as well.

In general, I would have to say that it is a Theory, and as such certain kinks are inevitable.

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Doesn't an instantaneous action at a distance require an infinite speed?

Is a stationary object moving infinitely slow?

You can say 'instantaneous = infinitely fast' if you like, just like you can say 'not moving = infinitely slow'. But a theory doesnt automatically become invalid just because youve managed to rephrase it in a way that lets you include the word 'infinite'. I've seen people argue that the law of identity rules out instantenous travel, but I've no idea why this is the case. If things travel instantaneously, then thats just the way the universe is.

Edited by Hal
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Is a stationary object moving infinitely slow?

No, a stationary object is not moving at all (within a given frame of reference).

You can say 'instantaneous = infinitely fast' if you like, just like you can say 'not moving = infinitely slow'.
Velocity is a measure of distance traveled over elapsed time. V = D/T. If an object is stationary, then D = 0 and the expression = 0 for any value of T. If D is some positive value and T is zero, then the expression has no meaning.

But a theory doesnt automatically become invalid just because youve managed to rephrase it in a way that lets you include the word 'infinite'.
I did not rephrase anything. I asked Travis a question to confirm what he meant by "instantaneous".

I am not a physicist, but I would say that any theory that depends on the ability of something to move with infinite speed has some explaining to do.

I've seen people argue that the law of identity rules out instantenous travel, but I've no idea why this is the case. If things travel instantaneously, then thats just the way the universe is.
Instantaneous travel would mean that an object exists at its departure point and it exists at its arrival point at the same time. It means one object becomes two objects, which would be the creation of matter out of nothing. I am not aware of anything that suggests such a possibility; absent any supporting evidence, the notion of instantaneous travel is as arbitrary as the notion of god.
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I am not a physicist, so I can not address your points coherently. Stephen Speicher, on the FORUM for Ayn Rand Fans, is who you should be talking to. If you go to the website, send him a PM, and see if you can get in touch with Dr. Lewis as well.

In general, I would have to say that it is a Theory, and as such certain kinks are inevitable.

I have a long history of debating this issue with those two. At this point I have no desire to talk to them further, and I'm *certain* they feel the same way about me.

Did you mean to imply that I was confused about something and that Speicher or Little could clarify it for me? I'm pretty sure that's wrong on both counts. But of course if you're not a physicist, I don't expect you to be able to judge which side is right in this debate. I only wanted to make you aware that there is a debate, and that there do exist a number of very knowledgeable Objectivist physicists who regard TEW as foolish crackpot nonsense. And I would encourage you and others to take that into account before you publicly proselytize for the theory under the banner of Objectivism.

Edited by Free Thinker
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Is a stationary object moving infinitely slow?

You can say 'instantaneous = infinitely fast' if you like, just like you can say 'not moving = infinitely slow'. But a theory doesnt automatically become invalid just because youve managed to rephrase it in a way that lets you include the word 'infinite'. I've seen people argue that the law of identity rules out instantenous travel, but I've no idea why this is the case. If things travel instantaneously, then thats just the way the universe is.

This is a good point. I think I might disagree with you about velocity: if something is moving with a velocity, philosophy tells us that the velocity isn't infinity, because infinity isn't any particular velocity. But the broader point I agree with: philosophy can't tell us that there is something moving with a particular velocity. That's a question for physics.

A similar example I've used in the past is the following fallacious proof that there must be at least one giraffe in any given square mile of land. If there weren't any, then the local area per giraffe would be infinite -- a contradiction with the law of identity!

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This is a good point.  I think I might disagree with you about velocity:  if something is moving with a velocity, philosophy tells us that the velocity isn't infinity, because infinity isn't any particular velocity.  But the broader point I agree with:  philosophy can't tell us that there is something moving with a particular velocity.  That's a question for physics. 

If something travels instaneously then we do not have to say that it is moving with "infinite velocity" or "no particular velocity" - we could instead choose to revise our idea of velocity and say something like "the concept of velocity does not apply to objects/information which trasmit instaneously". It only really makes sense to talk about velocity in the context of an object which is moving with finite speed between point A and point B - if the travel was genuinelly instanteous then I dont think it would be correct to talk about 'velocity' when describing it (and we certainly shouldnt say that it has an 'infinite' or 'undetermined' velocity).

The philosophical problems only seem to arise when we conceptualise instantanous travel as being a 'limitiing case' of an object moving very fast, rather than as being something qualatively different. Its as if we have a picture in our head of an object moving between 2 points at faster and faster speeds, then we tell ourselves that no matter how fast it goes, it must take SOME time to travel the distance. But the problem only stems from us choosing to think of instaneous travel in terms of this particular picture - Zeno encountered a similar problem when he conceptualised moving between 2 points as a picture of Achilles "continually travelling half the distance" and was forced to conclude that motion was impossible because otherwise travelling a finite distance would necessitate doing something infinitely many times. But this paradox was not intrinsic to the concept of motion - it was just a feature of the peculiar way Zeno chose to think about it. I believe the same holds for instantaneous travel - if we can shake off our misleading picture of 'instaneous' being the limiting case of 'infinitely fast' then the philosophical objections will vanish, and it will become a purely scientific question. And as far as I know, science is still undecided.

A similar example I've used in the past is the following fallacious proof that there must be at least one giraffe in any given square mile of land. If there weren't any, then the local area per giraffe would be infinite -- a contradiction with the law of identity!
Yeah, this is a good example. Its important to seperate contradictions caused by particular ways which we conceptualise and describe things, with intrinsic contradictions in the concepts themselves.

AisA

Velocity is a measure of distance traveled over elapsed time. V = D/T. If an object is stationary, then D = 0 and the expression = 0 for any value of T. If D is some positive value and T is zero, then the expression has no meaning.

Indeed. But this only suggests that it is wrong to think of instaneous travel in terms of velocity. D/T does grow arbitrarily large if D is fixed and t->0, but D/0 is not infinite, it is undefined. This is what I mean by the (what I view as misleading) idea of thinking aobut instantenous speed as being a limiting concept

But this is a different sort of objection, since you seem to be suggesting that instaneous travel is incompatible with some equations of physics. And if this were true (and I dont think it is since afaik Bohmian mechanics is a consistent theory despite placing no upper bound on the 'speed' of information transmission) then this would be a good reason for discounting it. But this is a scientific objection, not a philosophical one. There might be good scientific reasons for rejecting instantaneous travel - I dont know enough about physics to comment one way or the other. However, I dont think there are any purely philosophical reasons for rejecting it.

Edited by Hal
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There might be good scientific reasons for rejecting instantaneous travel - I dont know enough about physics to comment one way or the other. However, I dont think there are any purely philosophical reasons for rejecting it.

I gave you a philosophical reason for rejecting it in post #30. Unless someone can show some evidence to suggest it is possible, the assertion that instantaneous travel is "a possibility" is arbitrary.
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I have a long history of debating this issue with those two.  At this point I have no desire to talk to them further, and I'm *certain* they feel the same way about me. 
Ok.

Did you mean to imply that I was confused about something and that Speicher or Little could clarify it for me?  

Yes and No. I mean that either you you could be wrong (in general), but it has to do with the fact you are dealing with a theory, not a law.

I only wanted to make you aware that there is a debate, and that there do exist a number of very knowledgeable Objectivist physicists who regard TEW as foolish crackpot nonsense.  And I would encourage you and others to take that into account before you publicly proselytize for the theory under the banner of Objectivism.

From my intial reading of Speicher's summary, it seeming to make sense. I speak only from my limited knowledge of the subject.

Edited by Free Thinker
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I only wanted to make you aware that there is a debate, and that there do exist a number of very knowledgeable Objectivist physicists who regard TEW as foolish crackpot nonsense. And I would encourage you and others to take that into account before you publicly proselytize for the theory under the banner of Objectivism. 

While I am not as knowledgeable about this as ttn, I also get the impression that TEW is a crackpot theory.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

With regard to Bohm's theory and Newton's theory:

A force acting instantaneously over a distance is not the same as an object moving instantly from one place to another.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

With regard to teleportation and time travel:

For an object to disappear from one event (place and time) and then reappear at another event, without something equivalent going the other way, would violate the conservation laws of: energy, linear momentum, angular momentum, and electric charge. It would require violating the known laws of physics, not only at the events of the disappearance and reappearance, but also throughout all space-time because General Relativity and Maxwell's equations link the gravitational field and electromagnetic field throughout space-time to all their sources.

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I gave you a philosophical reason for rejecting it in post #30.  Unless someone can show some evidence to suggest it is possible, the assertion that instantaneous travel is "a possibility" is arbitrary.

If you want to say its arbitrary, thats something entirely different from the normal claim that it 'violates the law of identity'. If your position is just that its arbitrary, thats fine.

What evidence do you believe there is for TEW out of interest? It has the exact same level of observational support as every other interpretation of quantum theory, and is surely equally arbitrary.

Edited by Hal
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If you want to say its arbitrary, thats something entirely different from the normal claim that it 'violates the law of identity'. If your position is just that its arbitrary, thats fine.

Being arbitrary is, in some ways, a more damning indictment than violating an axiom.

In any event, I am not familiar with the arguments you have encountered regarding the law of identity.

I can see an argument along the following lines: Instantaneous travel means that an object is both at its departure point and at its arrival point at the same time. However, if a thing is what it is, and not something else, at the same time and in the same respect, then a thing is also where it is, and not somewhere else, at the same time and in the same respect.

What evidence do you believe there is for TEW out of interest? It has the exact same level of observational support as every other interpretation of quantum theory, and is surely equally arbitrary.
What distinguishes TEW from *some* QM theories is that it does not violate the fundamental axioms of philosophy.

The problem with QM is not the "interpretations of quantum theory"; the problem is the interpretations of the experimental observations, certain of the interpretations, anyway. Modern skeptics have latched onto what they claim are "conclusions" of quantum mechanics to attack Objectivist metaphysics and epistemology.

We are told, for example, that the fact that things can be both particles and waves at the same time means that the law of identity does not hold. We are told that since a cat can be both dead and alive at the same time, and is only forced into one state or the other by our observations, then the primacy of existence does not hold and consciousness determines reality. We are told that since the act of measuring one property of a particle affects another property of that particle, that man's means of gaining knowledge is limited and uncertain.

(For what it is worth, Stephen Speicher has said repeatedly that the more "bizarre" interpretations of experimental observations are not held by many practicing physicists; that they are left at the door of the laboratory where the real science begins. )

TEW is an attempt to explain the experimental observations of QM within the confines of philosophic axioms. If it does not explain all of the experimental observations, then it is either incomplete or incorrect. Either way, its approach, i.e. its attempt to explain observations in compliance with the axioms of philosophy, is surely correct. The fact that we cannot, at the moment, explain certain experimental observations does not refute the axioms of philosophy. Nor does it justify an “anything goes” approach to forming a proper theory.

I don’t know if TEW is correct or not. Frankly, I have a difficult time believing it is “foolish crackpot nonsense”; I know it is not arbitrary.

I also have a difficult time believing that relativity is wrong. I understood that a vast amount of experimental evidence supported relativity. I suppose time will tell.

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...  I mean that either you you could be wrong (in general), but it has to do with the fact you are dealing with a theory, not a law.

From my intial reading of Speicher's summary, it seeming to make sense. I speack only from my limited knowledge of the subject.

Fair enough. Many years ago I too was seduced by what sounded like good philosophy in Little's writings, and assumed that the physics part was equally good. Now I know better, and now your "limited knolwedge" is less limited -- it includes the fact that some very knowledgeable experts in the field think that TEW is an embarrassment to Objectivism.

BTW, I don't know what point you were trying to make with a distinction between theory and law. Whatever you want to call it, TEW is just wrong, and the people who continue to advocate it do this out of negligent ignorance (or worse).

Edited by Free Thinker
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What distinguishes TEW  from *some* QM theories is that it does not violate the fundamental axioms of philosophy.

Neither does the flat earth theory.

TEW is an attempt to explain the experimental observations of QM within the confines of philosophic axioms.  If it does not explain all of the experimental observations, then it is either incomplete or incorrect.  Either way, its approach, i.e. its attempt to explain observations in compliance with the axioms of philosophy, is surely correct.  The fact that we cannot, at the moment, explain certain experimental observations does not refute the axioms of philosophy.

The problem isn't just that certain facts remain unexplained. That it doesn't explain everything is surely no valid objection to a theory! The problem is that the theory's whole reason for existing is misguided. Little thinks that the non-locality in Bohm's theory is a flaw. But Bell's theorem and the relevant experiments show that this is actually a feature, not a flaw. Local theories are ruled out by experiment. I think you're focusing too much on "the axioms of philosophy." Of course it's right that any physics theory which contradicts valid metaphysical principles should be rejected. But being consistent with metaphysics is hardly a *sufficient* condition for the truth of a theory. Not even close. So focus on epistemology -- e.g., does the theory integrate with everything else that is known? Is it true? Are its advocates rational in their advocacy?

I was also confused by your last sentence. It seems to be based on the premise that TEW is the only possible theory that is consistent with metaphysics. That's preposterous.

I don’t know if TEW is correct or not.  Frankly, I have a difficult time believing it is “foolish crackpot nonsense”; I know it is not arbitrary.
I agree. TEW is a perfectly meaningful theory. And it contradicts known facts. So it's false. Just like the flat earth theory.

I also have a difficult time believing that relativity is wrong.  I understood that a vast amount of experimental evidence supported relativity.  I suppose time will tell.

Yes, it's a very surprising conclusion. It's entirely proper to scrutinize Bell's argument and the relevant experiments very closely. But of course it would never be proper to evade that evidence.

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The problem is that the theory's whole reason for existing is misguided. Little thinks that the non-locality in Bohm's theory is a flaw. But Bell's theorem and the relevant experiments show that this is actually a feature, not a flaw. Local theories are ruled out by experiment.

Is the double-delayed-choice experiment, along with Bell's theorem, the only evidence against relativity? I am not arguing that the evidence should be ignored; I am only trying to get a feel for the volume of evidence for and against relativity.

I think you're focusing too much on "the axioms of philosophy."  Of course it's right that any physics theory which contradicts valid metaphysical principles should be rejected.  But being consistent with metaphysics is hardly a *sufficient* condition for the truth of a theory.  Not even close.
I agree. I have not argued that consistency with philosophic axioms is a sufficient condition, only a necessary one.

So focus on epistemology -- e.g., does the theory integrate with everything else that is known?  Is it true?  Are its advocates rational in their advocacy?
I also agree that this a the proper way to evaluate a theory. I spent a lot of time reading the exchanges between yourself and others on the TEW discussion list; unfortunately, I lack the technical expertise to follow the arguments beyond a certain point. However, I am well aware that some knowledgable Objectivists reject the theory, including yourself and David Harriman.

I was also confused by your last sentence.  It seems to be based on the premise that TEW is the only possible theory that is consistent with metaphysics.  That's preposterous.
No, I didn't mean to imply that TEW is the only possible theory that is consistent with metaphysics. It is simply the only one that I had heard of prior to these exchanges with you.

My primary interest, in this context, is in defending Objectivism against attacks based on mis-representations of quantum physics. If Bohm's theory is consistent with Objectivism, I would like to know more about. Can you point me to a layman’s explanation of Bohm's theory?

And is there a layman’s explanation of Bell’s theorem and the double-delayed-choice experiment – or whatever it is that rules out local causation?

Thanks.

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Is the double-delayed-choice experiment, along with Bell's theorem, the only evidence against relativity?

It's the only crisp and conclusive evidence, yes. But I think it's a mistake to view relativity as some sort of monolith which is either right or wrong. First, there is a crucial distinction between the formalism of relativity (Lorentz transformation equations, etc.) and Einstein's specific theory (including especially the so-called Principle of Relativity). All the formalism has worked well for 100 years and there's no reason to think it all has to be thrown in the trash. More likely it will turn out to all be perfectly valid, but to have a limited (i.e., not universal) domain of applicability. I think a better perspective than weighing the pro-relativity evidence against the con-relativity evidence, is to look for a worldview that integrates with all the relevant evidence. This seems to include both the failure of the Principle of Relativity as a fundamental statement about the causal structure of the world, but also an acknowledgement of Lorentz symmetry as a widespread and important (somehow emergent) phenomenon.

My primary interest, in this context, is in defending Objectivism against attacks based on mis-representations of quantum physics.  If Bohm's theory is consistent with Objectivism, I would like to know more about.  Can you point me to a layman’s explanation of Bohm's theory?

And is there a layman’s explanation of Bell’s theorem and the double-delayed-choice experiment – or whatever it is that rules out local causation?

There's a nice article by Sheldon Goldstein in the online Stanford Encyclopedia of Philosophy:

http://plato.stanford.edu/entries/qm-bohm

It discusses Bohm's theory in some detail and also dedicates an early section to Bell's Theorem. The best reference for quantum non-locality is Tim Maudlin's book "Quantum Non-Locality and Relativity." It's written for the intelligent layman and is really wonderful in terms of clarity and accuracy. Jim Cushing's book "Quantum Mechanics: Historical Contingency and the Copenhagen Hegemony" provides a nice historical perspective on Bohm's theory and is also very layman-accessible (but he doesn't quite get Bell's theorem correct and some of his views on history are a bit odd). There was also a very nice Scientific American article on Bohm's theory in the 90's, written by David Z Albert; I'm sure google would turn up the exact reference.

I want to clarify one other point. It's important to stress that TEW is simply ruled out by experiment -- that it is false. But the difference between TEW and Bohm's theory is not just that the former gets this one prediction wrong, while the latter gets it right. Bohm's theory is a legitimate scientific theory; it has a definite and clear mathematical structure, one can prove as a theorem that it agrees with the (empirically correct) predictions of non-relativistic QM, etc. TEW on the other hand is terribly vague: we have loose talk of "reverse waves", but no wave equation; the particles supposedly follow the waves back to the source deterministically, but there are no equations to describe this, and it only works that way when it does (e.g., not in cases of "hopping"); it was claimed but never proved that the theory agrees with standard QM (except in delayed-choice experiments?); it is claimed that the theory "explains" relativity, yet not only is this never proved, it is quite obviously untenable. In short, TEW is not the kind of thing that a rational physicist can even take seriously as a theory. In at least several places where it's clear, it's definitely wrong; but on the whole it's just too loose, too sketchy, to be taken seriously. That's why I refer to it with the word "crackpot" (in addition to pointing out that it's false). And that's why it's such an embarrassment to have people associating it with Objectivism. If it were just false, that would be one thing. But when it's not just wrong, but embarrassingly unserious, that is absolute poison. Which is why, although I obviously sympathize with your goal of defending Objectivism against attacks motivated by the most irrational interpretations of QM, I urge you not to base your defense of Objectivism on TEW. To whatever extent TEW's advocates succeed in making Objectivism and TEW into a "package", they render rejection of Objectivism *rational*. And that is not a good thing.

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Whoa, check this out:

http://www.objectivescience.com/articles/dh_tew.htm

Apparently David Harriman, who writes for ARI, this TEW doesn't work!! I might have to read what he says and consider revising my position.

Can anyone tell me what they think, in non-technical terms, is wrong with TEW?

BTY, here is a question. Where does Little provide evidence for the existence of Elementary Waves? I suppose I just took it for granted.

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It's the only crisp and conclusive evidence, yes.  But I think it's a mistake to view relativity as some sort of monolith which is either right or wrong.  First, there is a crucial distinction between the formalism of relativity (Lorentz transformation equations, etc.) and Einstein's specific theory (including especially the so-called Principle of Relativity).  All the formalism has worked well for 100 years and there's no reason to think it all has to be thrown in the trash.  More likely it will turn out to all be perfectly valid, but to have a limited (i.e., not universal) domain of applicability.

I'm confused; doesnt standard Quantum Field Theory already give a unification of quantum physics with special relativity, consistent with all experimental data? Would accepting Bohmian mechanics necessitate throwing out the last 70 years of physics?

As I said before, I dont know much modern physics.

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Whoa, check this out:

http://www.objectivescience.com/articles/dh_tew.htm

Can anyone tell me what they think, in non-technical terms, is wrong with TEW?

BTY, here is a question. Where does Little provide evidence for the existence of Elementary Waves? I suppose I just took it for granted.

You can ask Dr. Little this question at the Forum4AynRandFans. I also recommend that you read what he has to say about superluminal communication(which in this context I believe is the same as superluminal causation). Here is part of it:

Which gets us to what is certainly the most overwhelming objection to superluminal communication: it contradicts and requires the total rejection of the theory of special relativity.  Relativity theory has been confirmed by more experiments, and to a greater degree of accuracy, than perhaps any other theory in the history of science.  Superluminal communication contradicts the findings of all of these countless experiments.

Relativity theory is not merely a surface description of relations between experimental dial readings.  It is a thoroughly validated theory regarding the way things are in reality.  Anyone who claims relativity theory is false, as do the superluminalists, must begin by offering a valid alternative explanation for the thousands of experiments confirming it.

You can read the entire thing HERE. Edited by Free Thinker
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I'm confused; doesnt standard Quantum Field Theory already give a unification of quantum physics with special relativity, consistent with all experimental data? Would accepting Bohmian mechanics necessitate throwing out the last 70 years of physics?

This is a fairly complicated and subtle issue, so you'll have to be satisfied with some rough answers (unless you want to learn a lot more physics!). Let's start with non-relativistic QM. The orthodox theory ("OQM") is local in the sense that you can't (according to the theory) transmit information faster than light, but non-local in terms of the underlying dynamics. (Briefly, the randomness associated with the collapse of the wave function "masks" the non-locality, prevents it from being *used* by humans to build telephones.) Same with Bohm's theory: the underlying dynamics is non-local, but a kind of inevitable uncertainty in initial conditions prevents humans from being able to build faster-than-light telephones.

Now QFT: when people say that QFT is consistent with relativity, what they mean is a kind of extension of the "no telephones" idea from the last paragraph. The empirical predictions of QFT -- what you can actually measure in the lab -- obey the appropriate relativistic transformation equations. Yet, just like the non-relativistic theories, QFT is non-local at the level of its basic dynamics (and for the same reason as ordinary orthodox QM: in order to predict that experiments have definite outcomes, we need a "wave function collapse postulate" and this involves nonlocality). So... part of the answer to your question is that the claims that QM and relativity have already been reconciled (in the form of QFT) are just false.

This is really all just another way of saying what I've said before: Bell's theorem and the associated experiments prove that no viable theory can respect (what Bell called) "serious Lorentz invariance". I guess the new point is that this claim wasn't based on simply "forgetting" to consider something (QFT or whatever).

So do we have to throw away 70 years worth of physics? No and yes. Most of the formalism will no doubt survive in some form, e.g., some as-yet-not-fully-discovered "Bohmian" version of QFT will share many of the same equations as standard QFT but without giving a central and vague role to the "observer", without smuggling in the notion of a classical world, without the orthodox confusion over what is physical and what is mental, etc. But I think we do have to come to grips with the fact that relativity turns out not to be fundamental; since most people thought it *was*, that does imply the need for some pretty serious rethinking of (at least) 70 years worth of physics. The recipes physicists have cooked up to predict and understand experimental results are valid, and nothing is going to change that; but it seems those formulas have been fundamentally misunderstood this whole time. (To those who know the history of 20th century physics, this really isn't all that surprising.)

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You can ask Dr. Little this question at the Forum4AynRandFans.  I also recommend that you read what he has to say about superluminal communication(which in this context I believe is the same as superluminal causation). Here is part of it:

[...]

You can read the entire thing HERE.

There are a number of errors and obfuscations in that piece. I wrote a long private message to Little and several others at the time pointing these out. If anyone is interested, email me privately and I will forward you a copy.

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Can anyone tell me what they think, in non-technical terms, is wrong with TEW?

TEW begins by assuming that particles can be classified by a specifiying a single location in space. This is a claim that tries to force the classical notion of a particle into the quantum world. There is no basis for such a claim.

Also, I believe that these super luminal interactions are a conclusive argument for the infinite extent of a quantum particle, if one is given that relativity is accurate.

Edited by Free Thinker
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I assume that Objectivists reject Everett's interpretation of Quantum Mechanics. Can someone give a proof that it is incompatible with Objectivist Metaphysics?
I certainly reject it, but not based on any incompatibility with metaphysical principles. Generally, I think people are trying to get far too much out of metaphysics. Metaphysics isn't going to tell you which physics theory is correct and which is incorrect. Yes, it is in principle possible to veto some flagrantly garbled theory because it conflicts with the law of identity. But that is rare. I don't think one can do it with even something as bizarre as the many-worlds interpretation of QM. After all, that theory (in at least some of its versions) says that the world exists independent of us and has a definite state which evolves deterministically according to definite laws. Now this world is admittedly bizarre. It does not "look like" the familiar 3D world of material objects. But so what? Metaphysics doesn't tell us that perception gives us direct insight into the ultimate constituents or structure of the physical world, or that the ultimate theory of physics must involve 3 spatial dimensions, or that interaction between entities must take place via finite speed propagation of particles or waves, or anything like that. It says: what is, is. And that's about it.

Valid (epistemological) reasons for rejecting MWI include: that it is simply vague and ill-defined as a theory, that it fails to solve the problem that motivates its advocates to advocate it, that an incredible price in physical plausibility is paid for a very minor (or non-existent) increase in formal simplicity, and that a much much better alternative is known to exist (so that one simply cannot point to any evidence in support of the extravagent world postulated by MWI). These are the sorts of criteria that (good) professional physicists use to evaluate theories. Applying them requires a lot of knowledge: one has to know how a given theory really works, how it is formulated and which aspects are central, and how it relates to other alternative theories.

There is a name for the doctrine that one can skip all this hard work and instead infer the correct assessment of a theory directly from philosophy: rationalism.

I don't mean to pick on anyone here, but there is a rather vicious streak of rationalism among Objectivists interested in physics, especially those who are attracted to TEW. It was made explicit earlier that "consistency with metaphysics" is not a sufficient condition for the truth of a theory. But there exist a number of people (perhaps not here) who continue to advocate TEW *exclusively* on those grounds. I am thinking of people who don't really know any physics, have never heard of Bohm's theory, don't really know what's wrong with other interpretations of QM such as MWI or the Copenhagen approach -- yet they support TEW because it "sounds good". ...which means, for all they can tell, it doesn't contradict the law of identity. Well I just want to stress, as clearly as I can, that this is nothing but total and complete rationalism. If you find yourself regularly advocating or rejecting detailed scientific theories on metaphysical grounds alone, you suffer from rationalism.

Speaking of rationalism...

TEW begins by assuming that particles can be classified by a specifiying a single location in space.  This is a claim that tries to force the classical notion of a particle into the quantum world.

This is *not* the reason why TEW is wrong. It is entirely possible to "force the classical notion of a particle into the quantum world" -- as proved a long time ago by de Broglie and Bohm. Anyone who thinks that this is the fundamental flaw in TEW, does not understand quantum mechanics (and is obviously ignorant of Bohmian Mechanics) and certainly does not sufficiently understand TEW either.

This is really the point I am concerned to make on this thread: if you don't know enough physics to know, at least in essential terms, how TEW works and how it is supposed to differ from other versions of quantum theory, you are simply not in a position to have an opinion on the theory. You shouldn't advocate it, and you also shouldn't say it's definitely wrong. Either claim would be totally unwarranted by the evidence actually present in your context of knowledge (and you shouldn't try to make up for that lack by relying heavily on metaphysics). I frankly don't understand why people are so desperate to have an opinion about this. If you don't know enough to have a valid opinion, you should refrain from having any opinion at all. Just like, for example, if you read one article by Ayn Rand but have never before heard of philosophy and don't know what any of the central philosophical questions are and how different people have attempted to answer them, it is premature to call yourself an Objectivist (i.e., to endorse Objectivism as true). In that position, you would simply need to learn more before you were in a position to have a position. Or take some random issue from, say, medical science: is some newly proposed procedure for performing some surgical operation better or worse than the older procedure? How the heck should any of us know? We simply don't have the knowledge necessary to take a stand one way or the other.

If only people would take that same attitude toward TEW, there would be no problem with this shameful crackpot junk being used by the ignorant to unwittingly undermine Objectivism.

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