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Albert's narrative argument against Everett-type theories

  1. Oct 2, 2011 #1
    I hope this didn't come up and I'm not just repeating it but I did a search and couldn't find anything on it. So, how convincing do others find Albert’s narrative argument against the advantages of Everett-type theories:

    If all this is right, then many-worlds and many-minds and many-histories theories have no advantage whatever - in so far as questions of Lorentz-invariance are concerned - over collapse theories. The Lorentz-invariance of many-worlds and many-minds and many-histories theories comes, after all, at the price of non-narratability - just as that of collapse theories does.

    http://philosophyfaculty.ucsd.edu/faculty/wuthrich/PhilPhys/AlbertDavid2008Man_PhysicsNarrative.pdf [Broken]

    Albert calls a theory narratable if specifying a system’s state at all times is sufficient to specify all properties of a system. Poincare-covariant quantum mechanics is not narratable: if we give the state at all times on a given foliation, we have given something less than the complete description of the system. One of the common arguments used in favour of the Everett interpretation over other interpretations is that it is fully compatible with special relativity. The conclusion Albert draws from narratability failure is that this presumed advantage is overstated.

    If he is correct, then if narratability failure is also acceptable in the Everett interpretation, why not in dynamical-collapse theories? On the other hand, if narratability failure is not acceptable, the only alternative is to give up on Lorentz covariance as fundamental and accept a preferred (albeit undetectable) foliation. But if this is acceptable in the Everett interpretation, why not in other interpretations (notably, hidden-variable theories like the Bohm theory, or non-covariant collapse theories)?


    http://philsci-archive.pitt.edu/4621/1/ststaterealism.pdf

    http://arxiv.org/PS_cache/arxiv/pdf/1002/1002.1726v1.pdf
     
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Oct 3, 2011 #2

    Demystifier

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    I agree that relativistic covariant quantum theories are not narrative. For example, the relativistic covariant version of Bohmian mechanics
    http://xxx.lanl.gov/abs/1002.3226 [Int. J. Quantum Inf. 9 (2011) 367-377]
    is based on a many-time wave function and therefore non-narrative.

    But the advantage of MWI over other interpretations is supposed to be something else, not Lorentz invariance.
     
  4. Oct 3, 2011 #3
    Well I'm not so sure about that statement.
    They play the "Lorentz invariant" card quite a lot, without it MWI is no better than Bohm.
    Actually it's worse than Bohm as Bohm can derive Born Rule and they can't :)
     
  5. Oct 3, 2011 #4

    Demystifier

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    I would put it this way:
    They say that MWI is better then Bohm because MWI requires a smaller number of assumptions.
    But what they usually omit to say is the fact that with this smaller number of assumptions they cannot derive the Born rule. To derive it they need to introduce some additional assumptions (e.g., certain decision-theoretic ones), but then the number of assumptions is no longer smaller than that for Bohm.

    Concerning the (non)-narrative nature of MWI, it should be emphasized that the usual formulation of MWI is narrative and not Lorentz invariant, simply because it is based on a single-time wave function. To save Lorentz invariance one must abandon the usual formulation and introduce a many-time wave function, which makes the theory non-narrative.
     
  6. Oct 30, 2011 #5
    Demystifier:

    What's your opinion of Tumulka's relativistic version of GRW (flash ontology version)? It is non-local but seems like the only "realist" formulation that is compatble with relativity. So I'm assuming here that this version is both narrative and Lorenz invariant?

    http://arxiv.org/PS_cache/quant-ph/pdf/0406/0406094v2.pdf
    http://www.maphy.uni-tuebingen.de/members/rotu/papers/losinj.pdf [Broken]
    http://www.maphy.uni-tuebingen.de/members/rotu/papers/bmgrw.pdf [Broken]
     
    Last edited by a moderator: May 5, 2017
  7. Oct 31, 2011 #6

    Demystifier

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    This may be the only narrative "realist" Lorentz invariant formulation currently known, but as I indicated in post #2, there is also a Bohmian non-narrative "realist" Lorenz invariant formulation.
     
  8. Nov 8, 2011 #7
    Thanks. Looks like another Lorentz invariant "realist" model has been produced:

    http://arxiv.org/PS_cache/arxiv/pdf/1111/1111.1425v1.pdf
     
  9. Jan 8, 2012 #8
    I came across this interesting paper looking at Albert's "narrative" argument in more detail. An interesting quote from Albert in Myrvold's piece:

    Thus, Albert, like Valentini, seems very critical of attempts to unite special relativity with QM, "calling it a ‘trick’ by means of which the theory is made ‘formally compatible with special relativity’ (Albert [2000], p. 6). Such merely formal compatibility, according to Albert, pays a high price:

    Relativistic Quantum Becoming
    http://publish.uwo.ca/~wmyrvold/RQB.pdf
     
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