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Does quantum theory make bizarre events possible?

  1. Jun 30, 2005 #1
    Michio Kaku appeared on Part 1 of Einstein's Unfinished Symphony with the following interpretation of probabilities in quantum mechanics:

    Wouldn’t this be impossible, even in principle? Mars at its closest is at a distance of 55.7 million km, and if particles are limited by the speed of light, wouldn't it mean that this event could never happen?
     
  2. jcsd
  3. Jun 30, 2005 #2
    OK, nobody believes in teleporting to Mars. I once read that physicists had managed to tunnel photons across a potential barrier to transmit a signal fractionally faster than usual.

    Even if, as far as anyone could tell, Newtonian physics were always obeyed universally, then there is always some possibility that something bizarre might happen which doesn't obey those laws. This is because scientific laws are our model of reality based on our experiences in a tiny fraction of the universe's life, in a tiny corner of the cosmos. It was never certain that these laws would always hold.

    The above thinking makes me feel at home with the concept that anything is possible (for all we know) and always will be. Can we really say what reality is? To me, quantum mechanics just captures our ignorance in a mathematical framework. A framework for predictions based on probabilities seems to me to be more credible than an arrogant pronouncement of knowlege.
     
  4. Jun 30, 2005 #3
    Of course, the discovery of quantum mechanics should make us more certain of most things than we ever had reason to be before. :biggrin:
     
  5. Jun 30, 2005 #4

    vanesch

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    It happens to me often on a saturday night, so I don't know where the problem is (except for the headache on sunday morning, of course) :tongue2:

    cheers,
    Patrick.
     
  6. Jun 30, 2005 #5

    dlgoff

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    I hope you'll continue to return so you can help us all here on Sunday. Or should I view your sunday post with skepticism? :rofl:
     
  7. Jul 2, 2005 #6
    Michio Kaku is famous by his fantasy. He is a fanatic supporter of that bizarre "theory" called string theory. He is specially portioned for extracting bizarre or even wrong questions from good theories.
     
  8. Jul 2, 2005 #7
    As far as I can tell String Theory is a good theory.

    (The main problem everyone seems to point out is that unfortunately we can find no way of testing it).
     
    Last edited: Jul 2, 2005
  9. Jul 2, 2005 #8
    According to quantum mechanics (QM) it is possible, because QM does not postulate speed of light to be constant. But one of the main problems in QM are actually physical interpretation of the theory itself and "nonlocality" (try to search google for terms like "quantum entanglement"). Basically, it all comes down to conclusion that faster-than-light interaction IS possible, but doing that no information is transfered at a speed higher than speed of light. There are many interpretations of QM nowadays (you can try to search for stuff like "parallel worlds in QM", "David Bohm", "Copenhagen interpretation of QM", ... for more info, if you're really interested).
     
  10. Jul 2, 2005 #9
    String Theory Is The Poor Theory Of History

    Please don't insult serious people!! :mad: (*)

    String theory is a waste of time. All experimental predictions of past were shown to be false (begining with strong force predictions and finalizing with recent sound fiasco in cosmological issues). Currently, string theory is the most incorrect theory of history of physics with a diference of more than 50 orders of magnitude between predicted and measured values.

    Moreover, before to claim for new experimental data, string theory may explain all that is already known in the standard model and GR. Far from popular claims, string theory predicts/explains nothing of known physics after of more than 30 years of research. Wath is more, often one needs to know first others theories for guiding the "derivation": e.g. the derivation of GR from string theory.

    Moreover, it is easy to show that the basic of string M-theory is extremedly trivial and ineffective (the record of derivation achieved is fantastic, today one can predict/derive nothing and some recent papers claim that string theory cannot predict nothing due to vacuum degeneracy).

    Initially, I studied string M-theory, including very recent material like stwing or non-commutative M(atrix) theory. All was wrong, and often the math involved simply ridiculous one.

    E.g. Seiberg-Witten paper in non-commutative geometry and string theory is very simplistic from a mathematical point of view (specially when one already worked with the non commutative star products in the phase space representation of semigroups quantum mechanics). Thus, I remained perplexed of the low level of string literature (when compared with popular claims on books and conferences). In many aspects, string theory is outdated. This is claimed in many published papers and conferences. For example, in the last conference Quantum future, Claus Kiefer and Erich Joos said

    "this is even true for tentative frameworks such as GUT theories or superstring theory. Although the latter may seem ‘exotic’ in some of its aspects (containing D-branes, many spacetime dimensions, etc.), it is very traditional in the sense of the quantum theoretical formalism employed."

    Very traditional may be read "outdated" regarding, for instance, sophisticated experiments with fullerenes.

    I am astonished that the self-proclamed ultra-advanced NC string theory (a radical modification of usual string theory in fixed background/cosmologies) used, in the last decade, advanced math developed in other fields of science by Prigogine and the Brussels School in the 60s. The delay of the “ultra advanced” theory is of most than 30 years for a supposed "profound" theory that, in the words of Brian Greene, is providing us the most basic understanding of nature! This is, obviously, false, simply propaganda.

    The same situation arises in recent TFD Dp-brane theory. Today, string theorists are very excited with the new formalism (was unknown for them), but people that developed TFD in the past (were not string theorists) now are developing TFD II. Again, string M-theory is outdated, string theorists are very proud people with no idea of what is being done in other fields; that is the reason of the great failure of string theory as a TOE.

    What is correct in string theory (like a TOE)?

    Simply nothing!! It is a waste of time.

    Of course, the claim of that string theory quantizes gravity or predicts GR is false propaganda.

    String theorists are well known due to their falsification of true. Some scientists called them mafia.

    For example, in his Elegant Universe, Brian Greene explained to many laymen that the observed 4D geometry of universe was explained from string considerations or that the concept of pointlike particles was substituted by the concept of strings, for example.

    Curiously, he "forgot" to comment to public that string is an approximation and that the only known formulation of M-theory is a simple quantum mechanics of pointlike particles (D0-branes). All past stuff was completely wrong. Do you remember when string theorists claimed that universe was 26-dimensional?

    Ok, but can string theorists explain why universe look like 4D? According to Brian Greene popular book, that was explained by Brandenberger y Vafa.

    To the question

    - If these extra dimensions exist, does string theory offer any explanation of why there are apparently three space dimensions larger than the rest?

    Witten replied

    - That's a big problem that has to be explained. As of now, string theorists have no explanation of why there are three large dimensions as well as time, and the other dimensions are microscopic.

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

    P.S: With (*) i was being provocative :rofl: Of course, i think that you are just another victim of string theory propaganda.
     
    Last edited: Jul 2, 2005
  11. Jul 8, 2005 #10
    This doesn't seem to be the consensus of physicists.
     
  12. Jul 8, 2005 #11
    Unfortunately, many physicist believe that the lack of public enthusiasm for physics justifies lying in pop-science books.

    The consensus of physicists has nothing to do with the trash they publish in popular science books, such as the elegant universe.

    The reason string theory cannot be tested is not for lack of technology, but because string theory can't make physical predictions of any kind! (at this time)
     
  13. Jul 8, 2005 #12
    I recall this documentary, Einstein Quote here:Time is relative
    He confirmed that all matter was composed of molecules – an idea that at the time was controversial. And most famously of all, he published the paper 'On the electrodynamics of moving bodies'. It contained his Theory of Special Relativity and suggested that time - something that had always thought to be unchanging and absolute – was relative. It could speed up or slow down depending on the speed you were travelling. From this paper would come an additional three pages, finished in September of the same year, that would contain the derivation of e=mc², the most famous mathematical equation ever written, endquote.

    Gets to the core of a number of QM paradox's, all probability related. If one was to have a system-devise,(lets say that the devise contains a particle with a known decay rate of 20 seconds?)that decays at a known rate, place the system in a capsule and accelerate to a near light speed, then bring to a stop, the system decay rates would not match the 'Standard-Model' tried and tested experimental observation, the particle decay rates(effect)would be RELATIVE (cause) to the acceleration placed upon the system?

    The 'TIME' event would be variable, some decay rates would increase far beyond the limits of observation, and likewise,some decay rates would be de-creased, decreased to such an extent that no 'decay-rate' is observed, over any amount of Time.

    Just to show how moving bodies can have an unexpected value:http://news.bbc.co.uk/1/hi/sci/tech/4656567.stm

    the crater is a sort of 'decay-rate'!
     
    Last edited: Jul 8, 2005
  14. Jul 9, 2005 #13
    Consensus is for more than 1000 physicists

    Take the population of physicists and split it into three parts:

    A) String theorists.

    B) People working in other unified or quantum gravity approaches, e.g. loop theorists, Hawking, etc.

    C) Other physicists (e.g. condensed matter, decoherence, nonequilibrium, chaos, etc.)

    A great part of A believes in string theory (Witten, Greene, Vafa, Schwartz, etc.) another part does not believe in it but work in it because it IS popular and because funding for alternative theories is almost stopped (this part is mostly formed by students and people with no tenured position. Several students have talked with me and said that string theory is a waste of time but work in it before need a job :grumpy:.

    The most part of B broadly critiques string theory like a wrong approach to quantum gravity. For example, it is well known that loop theoreticians said in the past that string theory was not the correct approach to quantum gravity. They were correct and now even string theorists recognize that string theory is not the correct theory of quantum gravity. They claim that correct theory is M-theory (which is not a theory of strings) but also claim that nobody know what is M-theory.

    Hawking also believes that string theory has been oversold and now claim for a reconsideration of other theories.

    The most part of C rejects string theory, for example Zeh, people working in decoherence, Brussels School and several schools of irreversibility, chaos and complexity, people working in alternative theories as Filkestein and followers, noncommutative geometry and followers, Penrose and twistors community, Wald (that of famous book in GR) and other relativists are working in geometrodynamics, people like Feygenbaum (previously particle physicist) working in chaos and solving problems in real laboratories (e.g. oscillating reactions, map generation software, etc.) has ridiculed the aim of string theorists for obtaining a theory of everything because reductionism does not work in chaos.

    Recognized Nobel laureates like Feynman, Anderson, Dyson, etc, have openly critiqued string theory. The last was Anderson who said that "string theory was a futile exercise like physics".

    Smart people in other fields have also critiqued string theory. For example A. Lindé, one of best specialists in cosmology and inflation, showed some years ago that cosmological models based in string theory were wrong and incompatible with both experimental data and his own inflationary theory.

    People who initially believed in string theory now are changing the mind. For example, Greene quotes to Murray Gell-Mann who believed in string theory in the 80s. However in his popular “elegant” book, Greene "forget" (he often "forgets" stuff against string theory) that now Gell-Mann leaved the field and is working in his own approach inspired in path integral approach to QG (which is traditionally one of approaches to quantum gravity, see Wald textbook in GR).

    In the past, i said that string theory was especially simple without revolution. If one discover string theory FROM particle physics then the change is radical, but i was working in others very complex fields like TFD, Brussels theory, non-commutative geometry and deformed quantization, nonstandard analysis, etc. The change to string theory was especially simple, because string theory is trivial. For example, Calabi-Yau math is difficult when compared to flat 4D spacetime of particle physics, but elementary when compared with spacetime foam models where manifold is not differentiable (CY is differentiable) or manifolds where time is not represented in terms of real number and one needs to appeal to hiperreal numers or more general math, etc.

    String theorists have no idea of these fields. The work of Witten in math is standard from this point of view, and does not addresses generalizations of star products due to complex non-hermitian parts of spacetime topology (because complex questions are ignored in string theory) or similar stuff. This is reason that mathematicians working in TGD or in non-commutative geometry are little impressed of string or M-theory math. In fact, there are mathematicians working in theories more general that recent M-theory. The idea of that M-theory is in the cutting edge of math is another piece of string theory propaganda.

    This year, after of receiving the Nobel for physics 2004, Gross, one of leaders of string theory, has recognized in public that string theory is not a revolution, since almost all of underlying physics is maintained intact. Compare that with the Brussels School theory where basic ideas of quantum mechanics (string theory is a simple quantum mechanics of strings) are generalized at a high mathematical level. The math involved in Prigogine theory is very difficult. In fact, some string theorists, e.g. Nanopoulos, have done irrelevant attempts to copy that math into a new radical string theory (so called non critical string theory). However, only the most elementary part (developed in the 60s :bugeye: ) is copied NOW, Moreover, it is copied incorrectly, the equations are completely wrong. Brussels School members are still doing mocking of that and, moreover, all modern work developed (in the 90s and presented in one of last Solvay conferences devoted to the field) is systematically ignored by string theorists.

    Of course, in arrogant books like Elegant Universe, people continue to receive a distorted view of the field.

    1st Final Note: string community is around 1000 physicists. Therefore, they are a minority. There is no consensus.

    2nd Final Note: a thing are the claims said for public (propaganda) and other thing is that is said in scientific talks, papers, etc. Look, for example, M. Kaku has recently said in an Einstein Symposium the last June:

    "String theory has been moving backwards, since it was accidentally discovered in 1968. "

    and compare with his popular books and conferences.


    Here more data in why string theory is
    a waste of time
     
    Last edited: Jul 9, 2005
  15. Jul 9, 2005 #14

    ZapperZ

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    I would rather that this thread not meander into a debate on "String Theory", because we DO have a section to do that here on PF. If this continues, I will have to figure out my skills on how I can split up this thread and move the relevant postings into that section of PF. And trust me, you don't want me to do that because I could EASILY butcher this thread accidentally!

    :)

    Furthermore, and this is highly my personal opinion, string theory is NOT quantum mechanics. Thus, the inclusion of it in this thread based on the OP question is not relevant.

    Zz.
     
    Last edited: Jul 9, 2005
  16. Jul 9, 2005 #15

    selfAdjoint

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    This is an astounding opinion. Strings are quantized, no? First-quantized in fact. How can they not be a part of quantum mechanics?
     
  17. Jul 9, 2005 #16

    ZapperZ

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    Standing waves are "quantized" also. It doesn't automatically mean it is a "part" of QM. Quantization is neither a criteria nor requirement to be a part of QM (energy level in a metal's conduction band is not quantized or discrete).

    String theory goes BEYOND QM. That's the whole impetus of that field. It should rederive all of QM (and GR), but just like SR is a generalized version of Newtonian laws but is NOT newtonian physics, so is string theory.

    Zz.
     
  18. Jul 10, 2005 #17
    Ok, i simply replied to a question on Kaku and others in strings-Kaku again.


    Take a basic course in string theory. The equation for a string is derived from the action and next quantized with usual techniques.

    string theory is a quantum theory of strings in 10 D.

    The only known formulation of M theory is a quantum theory of D0-branes in 11 D.
     
  19. Jul 10, 2005 #18
    Of course than no!! It is a simple QM; superposition principle, wave function states, and Hilbert-Fock math are maintained intact. It is more, the quantum mechanical part of string theory is specially simple and trivial when compared with other theories and researchs.

    For example, in the last conference Quantum future, Claus Kiefer and Erich Joos said

    "this is even true for tentative frameworks such as GUT theories or superstring theory. Although the latter may seem 'exotic' in some of its aspects (containing D-branes, many spacetime dimensions, etc.), it is very traditional in the sense of the quantum theoretical formalism employed."

    In fact, one of more recent (90s) revolutionary modifications of string theory has been the modification of quantum formalism used, from a copy of TFD. TFD theory was not developed by string theorists, but now is being applied to a generalization of old ("archaic") quantum mechanics of strings (the recent TFD-Dp-brane theory).

    Other example is non-critical string theory where revolutionary quantum approaches (e.g. generalization of QM by Prigogine) is being used for generalizing the old critical theory of Witten, Schwartz, Greene, Vafa, etc.

    The idea of string theory is in the cuting edge of math and physicis is another piece of string theory propaganda. The only revolution of string theory is the substitution of particles by strings and the use of hidden dimensions. The rest is standard. I said this years ago, now the 2004 Nobel laureate Gross (particle and string physicist) also sustains it

    NOVA: Does string theory constitute a revolution in physics?

    Gross: "We've replaced particles with strings—that in a sense is the most revolutionary aspect of the theory. But all of the other concepts of physics have been left untouched—a safe thing to do if you're making changes."
     
    Last edited: Jul 10, 2005
  20. Jul 10, 2005 #19

    ZapperZ

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    First of all, note that I said that it was a highly personal opinion. I make no bones of the fact that this is how I perceived it, rather than what it is professionally.

    Secondly, you can't just use the fact that something has the same starting form, and thus, it must be the same thing. Both classical and quantum mechanics have "Hamiltonians" as starting points. No one would call them to be the "same" thing.

    Thirdly, I do not wish to be told of your displeasure with string theory (if you had looked at my old postings in the string section of PF, I've said even more pointed criticism against this field than what you have). Again, this ISN'T the place to do it. If ALL people can come up with in response to the OP's question is "string theory", then it is a sad commentary on the understanding of basic QM and developments in physics. There are TONS of "weird" predictions of QM that have been empirically verified! Let's start with those!

    Zz.
     
  21. Jul 10, 2005 #20
    Ok, but i think that if anyone says his/her personal opinion here I can rebate it because is a open forum. I mean that string theory is a QM of strings, the strings are first/second quantized. In M theory only first quantized, the D0-branes.

    I said not that. String theory is a quantum theory because follows principles of quantum mechanics like superposition, wave function states, quantization of observables, etc. My emphasis on usual quantization procedure was for readers could see that string theory (a quantum theory of strings) was a copy of QFT (a quantum theory of fields).

    In a talk Weinberg said

    "Response to comment from audience: Yes, they were really doing string
    theory, so in this sense string theory is earlier than quantum field theory."

    Moreover, in classical mechanics the Hamiltonian is classical and quantum in the quantum mechanics, somewhat like one begins from classical string action and quantize it in usual approach. I meaned that.

    Ok.
     
    Last edited: Jul 10, 2005
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