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ttn

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  1. After re-reading this thread this morning, I have a couple of quick additional thoughts.

    1. Some of noumenalself's original formulations leave open the possibility of the erroneous view I was criticizing before. I am thinking specifically of the word "relevant" in statements like: "If none of the relevant evidence supports the possibility that a conclusion is wrong, the conclusion is certain." This could mean either "if none of the available evidence supports [doubt], the conclusion is certain" or "if the available evidence satisfies the relevant standard of proof, then the conclusion is certain." I think the latter formulation is correct. The former is what I took Dan Edge to be saying before. It dispenses with the idea of objective standards of proof and instead makes "certainty" subjective by defining it in terms of the evidence one happens to have at present (rather than the body of evidence that would be objectively sufficient to warrant the conclusion).

    2. A nice example (nicer, that is, than ET) might be the following: what should a rational person have said in Newton's time (say) about the possibility that there existed additional planets beyond Saturn? (At that time, the heliocentric solar system was established, but only Mercury, Venus, Earth, Mars, Jupiter, and Saturn were known about.) Here, I think, it is pretty clear that it wouldn't have been reasonable to say something like "within the context of my knowledge, I am 100% certain that there are no more planets beyond Saturn." Of course, if what that statement means is "I don't currently know of any planets beyond Saturn" it is true. But the statement at least poses as making a stronger claim, one that is about the actual existence (or not) of certain real entities out there in the world. So, at best, it is ambiguous. (But I think it's actually worse than that, since the ambiguity is essentially deliberate -- the statement is an attempt to make a claim about reality while simultaneously protecting oneself by not doing so -- i.e., an attempt to cover, by retreating to subjectivity, the fact that one doesn't actually have the evidence that would be needed to support the claim one is sort-of making.)

    Anyway, what is the reasonable position on this question in this context? I think the reasonable position is to assent to neither proposition ("there are planets beyond saturn" and "there aren't planets beyond saturn"). The existence of as-yet-undiscovered planets is a sensible, non-arbitrary hypothesis. (As opposed to "there are gremlins on venus" or "jesus, son of god, died for our sins".) But one shouldn't believe in such planets until there is some direct, positive evidence to support that conclusion. And likewise, one shouldn't believe there aren't such planets until there is some direct, positive evidence to support that conclusion (say, some kind of systematic survey -- of a sort that wouldn't even have been possible in Newton's time -- which finds nothing). The attitude here is similar, I think, to the one noumenalself has recently advertised elsewhere in regard to claims about global warming. Speaking for myself, I do not believe either that "human-produced CO2 is causing the earth to warm" or that "human-produced CO2 is not causing the earth to warm." (Note, of course, that this position is consistent with being a skeptic about the first claim. You don't have to establish the second proposition in order to see and say that the evidence allegedly proving the first proposition is dubious, insufficient, etc. This would be parallel, in the Newton/planets example, to arguing against some numerological crackpot who claims that there must be additional planets because 10 is god's favorite number and so he would of course have created the solar system with 10 planets. One doesn't have to be able to prove that there are no more planets, just to point out that that argument for additional planets is invalid... obviously.)

    3. Saying "a certain idea X advocated recently by Y is false and inconsistent with Z... now let me explain why" is not ad hominem and is not poisoning the well -- even if Y is upset by the accusation.

  2. mrocktor wrote:

    "There are no intelligent space aliens" is supported by all the evidence we have (we have not detected life native to anywhere but Earth, much less intelligent life).

    In addition to what noumenalself already pointed out:

    "All the evidence we have" is not necessarily the same as "all of the evidence demanded by a standard of proof" -- which is what noumenalself originally (and correctly) said. For example, in a murder case, if the prosecution has established opportunity (but nothing has been said that speaks to motive or means) it'd be completely wrong to conclude that the defendant is guilty simply because "all the evidence we have" points in that direction. It's possible for all the evidence available to point toward a certain conclusion, and yet still for the evidence to be insufficient to warrant that conclusion.

    Of course, for "intelligent space aliens exist" (let alone "there aren't any") the relevant standard for certainty is less clear than it is for the murder example (and even there, "motive, means, and opportunity" is only schematic). So there is maybe some room for reasonable disagreement on that particular question (though I don't think anyone on this thread actually cares about that).

    On the other hand, I don't think this comment by Dan Edge is reasonable:

    I am 100% certain that, within the context of my knowledge, there is no intelligent alien life. I am as certain of this fact as I am of the Law of Identity.

    This represents a misunderstanding of the role of "context" in Objectivist epistemology. The point of saying that "knowledge is contextual" is emphatically not to convert all statements about reality ("there is no intelligent alien life") into statements about one's current level of knowledge ("I don't currently know of any intelligent alien life") thus rendering them invincible from later disproof. See Rand's discussion of the rejection of the ether in the philosophy of science part of the ITOE appendices. As above, the crucial question is: what evidence would be required to establish conclusively that there is no intelligent alien life? The mere fact that we haven't yet discovered ET doesn't just magically, automatically, constitute satisfaction of that standard (whatever it is).

  3. Hello!

    I'm having some trouble with my physics research and I was hoping someone here might be able to help.

    Does anyone know where I can get a copy of this:

    Electrons et Photons: Rapports et Discussions du Cinquième Conseil de Physique tenu à Bruxelles du 24 au 29 Octobre 1927 sous les Auspices de l'Institut International de Physique Solvay, Gauthier-Villars, Paris (1928)

    It doesn't matter if it's in French or an English translation, but I haven't been able to find anything.

    I'd appreciate any help you can give. Thanks.

    A new book-length analysis of this conference (including full English translations of the talks and discussion) is coming out next year. But you're in luck: a pre-print version is available for free here

    http://www.arxiv.org/abs/quant-ph/0609184

    Highly recommended for anyone interested in quantum physics!

  4. A good chunk of this material (Bell's Theorem, Bohm's theory, nonlocality, TEW, etc.) was covered in some detail in a thread here about a year ago:

    http://forum.ObjectivismOnline.com/index.p...topic=3957&st=0

    Those interested in the current thread might benefit from reviewing the old one. I would also like to offer a 2nd order appeal-to-authority: anybody reading this should take the comments of Eric Dennis very seriously. He is extremely knowledgeable about these issues, and it's clear (to this authority, at least) that some of the other posters here could learn a lot from him.

  5. I am a student of chemical physics at the university of minnesota (go gophers).  I am both interested in the topic and I may be teaching it someday.  (My interest in alternative theories is definitely more recreational and my research is more in solid state.) My first teacher of QM in the chemistry department said something like "dont try to make a picture of what is occurring" as a warning to the (usally highly visual) chemistry students.  I guess I am still rebelling against that advice, but I am not finding any clear answer.  Its not really a big deal, but there is a something that is occurring, and therefore some mental image of what is occurring must exist.

    I'm with you. A proper theory in physics should give a *physical* account of what's happening in physical processes, and this should be "visualizable" in some terms. (Maybe the physical processes postulated by the theory don't look like familiar things like billiard balls, but they should look like something, so to speak.) This is related to the point that a proper theory is not just formalism. It's important to have a formalism, because without that you've just got loose talk (e.g., TEW) -- but the formalism must be interpreted. A theory has to tell you what the formalism means, what the equations in the theory are *about*. And as soon as it's clear what the theory is about, you should be able to "visualize" those things and their actions.

    I am curious to know which books you find particularily insightful (orthodox QM or otherwise).  I may get the time to read them one of these years.
    The best not-too-technical presentation of the fundamental interpretive problems with QM and the various possibilities for addressing them (that is, the various theories I listed before) is David Albert's book "Quantum Mechanics and Experience." It gets a bit weird at times (when he raises questions about how consciousness fits into all these theoretical models) and his writing style is unique. (I love it, but many people can't stand it.) That might be a good place to start.

    Jim Baggott's book "The Meaning of Quantum Theory" is also pretty good. (I think there's a second edition of that out now with a different title. "Beyond measure" maybe?)

    If you want a visualizable model of QM, then you need to study Bohmian Mechanics. The article by S. Goldstein at plato.stanford.edu is excellent. Jim Cushing's "Quantum Mechanics: Historical Contingency and the Copenhagen Hegemony" gives a very nice historical survey. Bohm and Hiley's "The Undivided Universe" is a fairly readable textbook-type presentation of the theory. Holland's "The Quantum Theory of Motion" is a denser textbook-style presentation. And I can't recommend Bell's papers (collected in the book "Speakable and Unspeakable") highly enough. He is an amazingly clear thinker and writer, and is almost 100% responsible for the resurgence in interest in Bohm's theory in the last couple of decades.

    On a shorter timescale, maybe you'd enjoy some of these papers:

    http://www.arxiv.org/find/quant-ph/1/au:+n...ec7c3c560531df1

    ... This is beginning to sound very epistemological.  ...

    Good. That was the perspective I meant to argue for before when I tiraded against rationalism. If you want to know which theory in physics is true, metaphysics just isn't going to tell you. The question is fundamentally epistemological, and there is no valid "short cut".

  6. Thanks, it looks like I have a little reading to do.

    Why bother? Not that I don't think you should; I'm just curious about your motivation. Are you a physics student or just interested in the subject or...?? Anyway, let me know if I can help suggest something. There's a lot of crap on this topic out there.

    All models aside, what would you say would constitute a philosophically valid model of quantum mechanics?  I would say the following has to be true of such a theory:

    Deterministic causality of particle motion

    A Definite state of a particle

    Corresponds with experimental evidence

    (I say philosophically valid because I just lumped everything associated with correct physics into the experimental evidence part)

    That's a very difficult question. I don't strongly disagree with what you say, though I think "corresponds with experimental evidence" needs to be fleshed out significantly. I mean, it's certainly correct that a theory must be consistent with experiment, but there is more to it than that -- the theory needs to emerge in a certain way from a rational organization and essentialization of the evidence. But saying exactly how this ought to work is equivalent to giving a detailed theory about how induction works in physics, something I'm not in a position to do in this post...

    Also, I don't think there's a lot to your other two criteria. I wouldn't require a theory to be deterministic. It's a theorem that any stochastic theory can be turned into a deterministic theory by adding hidden variables. (What's not true is that a non-local stochastic theory like OQM can be made into a local hidden variables theory!) So determinism just isn't a big issue. I suppose you meant that if a theory claimed explicitly that its randomness was fundamental, a philosopher might object to that. But I think a better objection is simply that, given the theorem I mentioned, there cannot possibly be a basis for the claim that the randomness is irreducible. So any such claim should be rejected, not on metaphysical grounds per se but on the grounds that there would be no evidence for the claim. Finally, it's not clear to me what you mean by the requirement that the theory attribute definite states to the particles (or whatever). I can't think of any theory (among the ones I mentioned before) that would fail this test. I mean, a theory which says that the wave function is all that really exists, will attribute a "definite state" to particles -- e.g., the particle is in a superposition of being over here and over there. That's only not a definite state if you smuggle in some notion of what a definite state ought to look like... which is equivalent to smuggling in your own theory and then dismissing the one in question because it's different. But that, obviously, isn't the same as "philosophy requires such and such".

  7. If one thinks that energetic interactions that constitute causal mechanisms between two particles travel in space at a finite speed (for example light waves) then, to determine that speed, one must define an interparticle distance.  There need not be an interaction that travels faster than the speed of light in the case of entanglement if the two particles cannot be definitively separated.

    I understand the picture you have in mind, but let's be clear about something. Do you think that the derivation of Bell's Inequality somehow assumes a "little dot" model of particles? It doesn't. It doesn't assume any physics model at all. It's just statistics, based on the assumption that the outcome on one side of the experiment doesn't depend on the final settings on the far side. So if the inequality is violated experimentally, the outcome on one side *does* depend on the setting on the other side, and you can put a lower limit on the speed involved (assuming for the moment that there even is a "signal" which propagates with some speed) based on features of the experiment in question (namely, how far apart the two sides are and how long before each outcome is registered the distant setting is set).

    That there is superluminal causation is simply an empirical fact. You can't make it go away with some kind of non-little-dot model of the particles. What you *might* do is argue that, based on some plausible model, it doesn't make sense to talk in terms of particles interacting by sending finite-speed signals back and forth. You might have a model in which there aren't really two distinct spatially separated entities, but, rather, one unified blob which extends across the whole region of space where the two detectors are located. And in such a model perhaps it would be appropriate to speak of the "blob" responding as a whole when one corner of it gets tweaked in a certain way (thus rendering talk of the "speed" of "signal propagation" inappropriate). But strictly speaking this still violates relativistic causality. If you've got a hunk of stuff and whacking one end makes the other end jiggle, then it's equally problematic for relativity whether a pressure wave propagates through the stuff at a million times c, or if, instead, the whole hunk "rings" simultaneously the instant the one end is struck. In both cases, something happens over there before a light signal from here could get there, so the idea of effects living exclusively inside the future light cone of causes is out.

    In other words, the idea of superluminal causation (defined as packets of force that travel faster than light from one partricle to another) requires the boundary of each particle clearly defined.  Should the ultimate constituients of matter actually resemble waves, this boundary is not clearly defined (nor should it be).  In such a case, an interaction between the waves that is a result of physical contact of the two waves can occur instantaneously betwen two waves whose centers are quite separate.

    Not to dwell on this, but if you wanted to take it seriously, you'd basically have to say that in these EPR/Bell experiments, although "particles are detected" at the locations of the two detectors, the causally-relevant parts of the particles are located (right next to each other) in some other spatial region -- say, midway between the detectors where their respective edges touch. In other words, you have a problem explaining how anything gets registered at the detectors.

    But this is all really beside the point. If the question is whether relativity's prohibition on superluminal causation is respected by nature, it isn't, and you don't need to consider any particular physical model of particles to know that. That's why Bell's Theorem is so amazingly cool. On the other hand, if the question is whether this particular theory of yours is viable, I think you have some more fleshing out to do before anyone can possibly answer that question.

    Also, could you give me some kind of a list of the different quantum theories that you have read, along with a quick description of them?

    Well, there's the "copenhagen interpretation" which I wouldn't even mention as a serious theory except that it's been the orthodoxy for almost 100 years. Then there is the de Broglie - Bohm theory, which I have discussed already. It is, I think, quite clearly the most reasonable way of understanding quantum physics. There are some technical physics issues related to it (like whether it's possible to generalize it to more than just non-relativistic QM) but I don't think there are any legitimate philosophic objections to it. Then there is the many worlds interpretation (MWI) which comes in several different versions including the so-called Many Minds Interpretation. Most versions of this are either ill-defined or solipsist -- and in either case I find them too crazy to take seriously. Finally there is the GRW type theories I mentioned before. That's about it, really. There are some fringe interpretations like Cramer's "transactional interpretation" (which tries to avoid faster-than-light causation by having backwards-in-time causality), but this just doesn't really work as a serious theory (for reasons pointed out in Maudlin's book, among others) and nobody in Foundations circles takes it very seriously. And there are some others at that same level. Then there are the crackpot theories you mention, which typically explain one obscure isolated phenomenon or two by the use of some strange ad hoc device which obviously does not work in general.

  8. Im not sure that is entirely correct.  Such superluminal causation seems to be something that is a result of assuming a finite and definite end to a particle.

    No, it isn't.

    I think that part of the problem with interpreting the double slit experiment (for example),  is that no formulation of QM (that I know of) describes the dynamics of electron localization at an elementary level (like F=ma type of undertanding).  I think such an understanding is necessary to avoid the fundamental indeterminism that is present in QM.

    Bohm's theory is deterministic, so it avoids the indeterminism of orthodox QM -- and there is no special need in Bohm's theory to explain "the dynamics of electron localization at an elementary level" since electrons just are localized particles. There is also a respectable pure-wave interpretation of QM called GRW (Ghirardi, Rimini, Weber, aka spontaneous collapse or spontaneous localization), but this theory is not deterministic.

  9. I think bell's response to the double slit experiment is well thought out and is a valid explanation of the interference pattern that is seen.

    I think Bell's point is that it's the most obvious way of making sense of the observed pattern. That doesn't mean it's the only way, and it doesn't prove that this ontology is correct, but it's surely a motivation to look for a more comprehensive theory that is based on this wave-guided-by-particle ontology. That such a theory exists and works, but is hardly known by physicists, is (on the face of it) an inexplicable mystery. Of course we know the explanation is that the founders of quantum theory were *looking* for something that was anti-common-sense and anti-realism.

    What I have a difficult time with is why a theory of elementary particles must first begin by assuming that particles are little dots.  It seems unnecessary and slightly rationalistic.
    I don't get what bothers you about "little dots." The evidence that particles are really particles (i.e., little "dots" of stuff that stay little as they move around) is "the smallness of the scintillation on the screen" (from Bell's quote)... and all the other countless bits of empirical evidence that particles really are particles. I don't think anyone wants to "first begin by assuming" that there exist particles; people think the constituents of atoms are particles because of actual empirical evidence. So i don't see what you think is rationalistic.

    I believe that the entanglement issue is the real trouble for a theory that makes the "little dot" assumption.  I think bohm tried to resolve the touble by explicitly placing non-local terms in his equation (correct me if i am wrong).  It seems funny to make such a claim.

    A couple points here. First, entanglement is no more a problem for a particle or particle-guided-by-wave theory, than it is for (say) a pure-wave theory. All "entanglement" means is that two spatially separated systems aren't physically independent -- the separated parts retain some kind of interaction despite the separation. So in a particle theory you just need the particles to interact. There's really no big "problem" there unless you are worried about the fact that the interaction will violate relativity's prohibition on superluminal causation -- that's a valid worry, but my point is that you'd have to worry about that same issue with a pure-wave theory too. Experimental violations of Bell's Inequality prove that nature violates Bell Locality -- i.e., that there is some kind of relativity-violating superluminal causation. It's not like you can avoid this by dropping the "little dot assumption."

    Second, it's true that there are non-local terms in Bohm's equation -- specifically, the trajectory of a given particle can be influenced by the goings-on at the location of a distant particle to which the first is entangled. That is, Bohm's theory has explicit non-local action at a distance. It's right there in the equations for all to see. But it's misleading to say that "bohm tried to resolve the trouble by" including this effect. This gets the history just backwards. In retrospect, Bohm did basically the obvious thing -- his equations are the obvious equations to supplement Schroedinger's equation with if you want to try to have a particles-guided-by-wave ontology. So he just wrote down those equations and then proved that the theory reproduces all the predictions of orthodox QM. Now, one of the reasons his theory wasn't taken very seriously was that it was explicitly nonlocal. People's attitude was "OK, so you found a hidden variable theory, but it violates relativity so it can't be right and we can all just ignore it." (This is a completely unjustified position since orthodox QM is *also* explicitly non-local, and it's too generous to the culture to say that people ignored Bohm's theory for this reason; mostly it was ignored for *no* reason -- i.e., it was just ignored; after all, it had been proved that a theory like Bohm's couldn't exist...)

    Bell was one of the first people to recognize the importance of what Bohm had done -- namely, constructed an actual *counterexample* to the "no hidden variable theory" proof that had been given by von Neumann. Bell's first paper on the foundations of QM is a probing analysis of von Neumann's old proof, which shows where that proof went wrong. (Bell wrote later that von Neumann's assumptions in that proof were not just false, but foolish -- and he had a very low opinion of the mentality of people who had taken it seriously.) So at this point Bell was very interested in the question: would it be possible to have a theory like Bohm's (in the sense of providing a clear, common-sense, realistic ontology for QM while reproducing all the correct predictions of the orthodox theory) but which respected relativistic causality? In a short time he was able to prove that it wasn't possible -- that theories respecting "Bell Locality" could never be made to agree with the predictions of QM.

    So it isn't that Bohm "fixed up" his equations to get them in line with the non-locality that Bell proved is really there. Rather, Bell discovered that the non-locality is really there precisely by trying to get rid of the non-locality that was present from day 1 in Bohm's theory (and eventually proving it couldn't be gotten rid of).

    What i think is ridiculous is the mystical interpretation that is given to current QM.  It seems to me that the posulate that fundamental particles act as waves does not necessarily imply that they do not have definite properties.

    I agree on both points. Mysticism is no good. And there is nothing inherently bad about a pure-wave interpretation of QM. Just because something we used to call a "particle" turns out really not to be a particle, doesn't mean the thing violates the law of identity or whatever. It just means we were wrong about its nature. So you could never veto a theory merely because it said that "fundamental paticles" are really waves.

    But there are several other reasons for rejecting this picture. By the way, this was precisely the picture Schroedinger originally had in mind when he discovered what we now call Sch's equation. He wanted to think of the wave function as describing the density of a really-smeared-out electron "blob". But that turns out to be untenable for technical reasons -- in particular, the equations say that the blobs should spread out significantly and quickly, yet we always see electrons at definite places (like in the 2 slit experiment), never smeared out over a finite region.

  10. Do you see the difference?

    These aren't the way scientists use these terms. The atomic theory of matter, for example, is not a mere conjecture or a mere possibility. But there's no point arguing about mere terminology.

    TEW may need revision, but not necessarily abandonment.

    The only "revision" that would save it would be to turn it into Bohmian Mechanics.

    ...i.e., it should be abandoned in favor of Bohmian Mechanics.

  11. [...] I just find it totally ridiculuous that people cling desparately to the notion of a particle as a little dot in space.  I just want to know why one needs to make this assumption when the results of so many experiments seem to contradict it. :)

    In another note, having an opinion does not make one a crackpot.  Whether or not you choose to think about what I am saying, dont think you have this problem solved, or insult others who are trying to form a hypothesis.

    I'm sorry, I think I misinterpreted your earlier comment. I thought you were objecting to treating particles as *points* (on the grounds that points are infinitely small and hence metaphysically impossible... or some such). But you're not objecting to particles as points (as opposed to tiny but finite sized lumps), right? You're objecting to particles as opposed to waves or something else that is spread out a *lot*.

    I still think that's a poor objection to TEW, but it isn't the rationalistic one I criticized you for, so I apologize.

    Now, re: particles vs. waves, what experiments do you have in mind that contradict the "notion of a particle as a little dot in space"? I find Bell's comment about the two slit experiment completely compelling:

    "Is it not clear from the smallness of the scintillation on the screen that we have to do with a particle? And is it not clear, from the diffraction and interference patterns, that the motion of the particle is directed by a wave? DeBroglie showed in detail how the motion of a particle, passing through just one of two holes in the screen, could be influenced by waves propagating through both holes. And so influenced that the particle does not go where the waves cancel out, but is attracted to where they cooperate. This idea seems to me so natural and simple, to resolve the wave-particle dilemma in such a clear and ordinary way, that it is a great mystery to me that it was so completely ignored."

    He is, of course, referring to Bohmian Mechanics, which de Broglie actually more or less discovered in 1927, but then subsequently rejected when he couldn't answer some objections that Pauli raised.

  12. This is a package deal.  While it is certainly true that metaphysics does not tell us that “perception gives us direct insight into the ultimate constituents”, metaphysics does tell us that only the finite exists.  There is no such thing as an infinite speed.

    I agree with you; there is no such speed as "infinity". What made you think I thought there was? Maybe you had an argument like this in mind: if two separated entities affect each other, it is because something flies from one to the other, thus if the effect occurs simultaneously with the cause, the something must fly with infinite speed. Then, since there's no such thing as infinite speed, it follows that "instantaneous action at a distance" is ruled out by metaphysics. But I don't think this argument works. It smuggles in an unproved premise -- namely, that something flies from one to the other.

    Metaphysics says more than “what is, is”.  It says contradictions cannot exist.  You cannot stretch it to say, “If the only inference from a particular experiment is that something propogates at an infinite speed, then it is what it is, and metaphysics has nothing else to say."
    I don't disagree with you. I disagree with the people who claim that what I advocate is tantamount to "something propagates at an infinite speed"!

    If we should not even say that it is wrong, then why are you going to such an effort to convince us that it is "shameful crackpot junk”?

    That's a fair question. I'm not really trying to convince anyone here that TEW is false. I'm just making my "expert opinion" more widely known, so that those people who don't have any firsthand knowledge (and hence must rely on the opinions of others) aren't fooled into thinking that TEW has widespread support among Objectivist experts. This relates to your next question...

    By the way, why did you drop out of the TEWLIP discussion?  And since TEW has been around for years, why are you now coming here to denounce it?

    I was kicked off TEWLIP (for pointing out the flaws in one of Little's attempts to explain these experiments, and some subsequent name-calling). I have also been kicked off of Speicher's "Forum" website, where I attempted to post something explaining what was wrong with TEW. Other knowledgeable Objectivists (e.g., Eric Dennis) have suffered the same fate. The way things stand now, any forum where discussion of TEW takes place has been systematically cleansed of dissenters. Hence, the only discussion that exists is highly biased; I worry that this leads non-experts to the false view that there are no dissenters, which hopefully explains my recent posts here.

    The one exception I know of to what I said in the previous paragraph is HBL. There was an exchange about TEW there a few months ago. And I think the outcomes there (especially combined with the "cleansing" mentioned above) speak for themselves. The TEW supporters have no answers to the criticisms, and have rather systematically retreated to a small dark corner where they talk amongst themselves and ensnare innocent victims.

    I hope some of my comments here will help people at least understand the lay of the land before they unwittingly support something bad.

  13. I'm certainly not against people using "common sense, guided by philosophical principles" to reject obviously ridiculous ideas. But there is a difference between rejecting the blatantly stupid (and even telling others that you reject it) and openly proselytizing for a specific theory in the absense of relevant knowledge -- specifically, in the absense of knowledge about the particular issues that distinguish the various alternative theories from one another. To use your example of teleporting bacteria, it is one thing to say "that sounds completely stupid to me and I don't believe it"... quite another to say "that sounds completely stupid to me and, as an alternative, I advocate this other theory that I just read about for 5 minutes on the internet even though I know there are 10 other theories out there too and I don't know anything about those."

    You mentioned that some people's motivation to proselytize for TEW is the desire "to dispose of ... a particular objection to Objectivism." I don't consider that a rational motivation (convincing others, I mean). If some random stranger really believes that quantum physics refutes Objectivism, is a brief mention of TEW or anything else really going to change his mind? And what is the point of even trying to change his mind? And on the off chance that the stranger actually knows something about physics, mentioning TEW will have precisely the opposite effect: it will only convince him that Objectivism really is refuted by QM (else why would Objectivists resort to an untenable theory?).

    So... I urge people one final time: if you don't know enough physics to be advocating TEW, please just stop advocating it. It's an embarrassment that undermines our shared cause.

  14. 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.

  15. 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.

  16. 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.)

  17. 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.

  18. 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.

  19. ...  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).

  20. 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!

  21. 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.

  22. 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.

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

    If something propagates from one particle to the other, yes. But I think you missed the main point. You should take the instantaneousness of the action at a distance in Bohm's theory exactly as seriously as you (would have) take(n) the instantaneousness of the action at a distance in Newton's gravity law. That is to say: you shouldn't take it seriously at all. Rather, you should take it as an approximation which can easily be modified in the future when there are some empirical grounds for believing in a particular speed. That's what I was getting at before when I asked if anyone would seriously think it rational to have rejected Newton's whole theory of gravitation on the grounds that, according to Newton's equation, the action at a distance was instantaneous.

    But there's also an even mainer main point. Bohm's theory has nothing to do with whether or not TEW is a viable theory. 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. Lewis Little's claims to have refuted this are not just wrong, but foolish -- and so it does real harm to the Objectivist cause when people proselytize, in public and qua Objectivists, for TEW.

  24. Dr. Lewis Little created of the "Theory of Elementary Waves". It answers both the Uncertainty Principle and the Schrodinger's cat paradox. The original paper can be found here.

    Stephen Speicher, co-founder of the FORUMS for Ayn Rand Fans (here), is also a physicist. He wrote a summary of the theory for a non-technical audience, found here.

    PRODOS, a radio host, has a website which facilitates discussion of the TEW, as well as links to other websites as well. That can be found here.

    A radio interview between PRODOS and Dr. Lewis can be found here.

    Please see my comments on this here.

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