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B Is there any interpretation covering this?

  1. Jun 22, 2016 #1
    I was wondering if it is possible that not only the past influences (or causes) the future, but also the converse, that the future influences the past. I imagine waves of probability propagating from the future into the past as well as from the past into the future, thereby influencing each other, for example interfering of even resonating with each other. Is there any interpretation (more or less) covering this?

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  3. Jun 22, 2016 #2


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    The Transactional Interpretation reasons along these lines. This Wikipedia link should get you started.
  4. Jun 22, 2016 #3
    Thank you! I've bumped into it before, but it apparently somehow escaped my attention. Probably because I was working on my own view and basic QM knowledge first. The transactional interpretation seems to be just what I was searching for! Thanks! :smile:
    Last edited: Jun 22, 2016
  5. Jun 22, 2016 #4


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  6. Jun 22, 2016 #5
    Hmmm, I'm not sure the transactional interpretation is exactly what I mean. But I guess it's the best approximation of what I mean. :biggrin: Anyway, what do I know? :-p

    Sorry for the little joke. :nb):biggrin:
    Last edited: Jun 22, 2016
  7. Jun 22, 2016 #6


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    BTW, Relational Blockworld considers itself to be acausal or bicausal with respect to time.
  8. Jun 22, 2016 #7
    That's interesting! But isn't blockworld a kind of superdeterministic model?
  9. Jun 23, 2016 #8


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    Nope. There is nothing "determining" the actual outcome.
  10. Jun 23, 2016 #9
    Is there any (free/public domain) publication or book I can best buy explaining TI with math, but not too complicated math?
    Last edited: Jun 23, 2016
  11. Jun 23, 2016 #10
  12. Jun 23, 2016 #11
    Some useful links on retrocausal explanations of quantum entanglement and beyond
    (13) Quantum Retrocausation III. Organizer: Daniel P. Sheehan (Department of Physics and Biophysics, University of San Diego, San Diego, California; dsheehan@sandiego.edu).
    Two day program, scheduled for Wednesday and Thursday, 15 and 16 June.

    Causation – the principle that earlier events affect later ones, but not vice versa – undergirds our experience of reality and physical law. Although it predicated on the forward unidirectionality of time, in fact, most physical laws are time symmetric; thus, they formally and equally admit both time-forward and time-reverse solutions. Time-reverse solutions suggest that, in principle, the future might influence the past, i.e., reverse (or retro-) causation. Why time-forward solutions are preferentially observed remains an unresolved problem. In-with journal citations increasing exponentially in recent years.

    Evidence for reverse causation is currently relatively scarce and controversial. While laboratory results are intriguing, theoretical models have lagged, not yet making solid connections with mainstream physics. Furthermore, many of the most basic physical issues – e.g., the role of the second law of thermodynamics in disallowing retrocausation, and whether retrocausation is best explained by energy transfers or simply by correlations without information exchange – remain open questions.

    This symposium will explore recent experiments, theory, and philosophical issues concerning retrocausation. It is hoped the meeting will foster better theoretical models by which laboratory results can be understood, and stimulate new experiments and collaborations by which the underlying physics may be more clearly exposed.


    • Frontiers of Time: Retrocausation – Experiment and Theory, D.P. Sheehan, Editor, AIP Conference Series, Volume 863, (AIP Press, Melville, NY, 2006).
    • Quantum Retrocausation: Theory and Experiment, D.P. Sheehan, Editor, AIP Conference Volume 1408 (American Institute of Physics, Melville, NY, 2011).
  13. Jun 24, 2016 #12


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    Thanks for this, that is quite a group of people presenting.
  14. Jun 24, 2016 #13
  15. Jun 24, 2016 #14
    Causal Symmetry and the Transactional Interpretation

    Peter W. Evans 14 April, 2012


    Cramer’s (1986) transactional interpretation of quantum mechanics posits retro- causal influences in quantum processes in an attempt to alleviate some of the inter- pretational difficulties of the Copenhagen interpretation. In response to Cramer’s theory, Maudlin (2002) has levelled a significant objection against any retrocausal model of quantum mechanics. I present here an examination of the transactional interpretation of quantum mechanics and an analysis of Maudlin’s critique. I claim that, although Maudlin correctly isolates the weaknesses of Cramer’s theory, his justification for this weakness is off the mark. The cardinal vice of the transac- tional interpretation is its failure to provide a sufficient causal structure to constrain uniquely the behaviour of quantum systems and I contend that this is due to a lack of causal symmetry in the theory. In contrast, Maudlin attributes this shortcomng to retrocausality itself and emphasises an apparently fundamental incongruence between retrocausality and his own metaphysical picture of reality. I conclude by arguing that the problematic aspect of this incongruence is Maudlin’s assumptions about what is appropriate for such a metaphysical picture.

    Key words: quantum mechanics, transactional interpretation, retrocausality

  16. Jul 1, 2016 #15
    You can check out my website for resources on TiQM: https://transactionalinterpretation.org
    However I should also point out that one has to be careful about what they mean by 'retrocausation'.
    In my version of TI there is a kind of retrocausal influence that is part of the process of emergence of spacetime events.
    However in a block world there isn't really room for any dynamical sort of causation--in that sense it can be viewed as 'superdeterministic'
    just in the sense that all events exist already, and therefore are not being brought about (i.e. caused) by an influence within spacetime itself.
  17. Jul 1, 2016 #16
    If we introduce MWI in this picture, one could escape superdeterminism, right?
  18. Jul 1, 2016 #17
    Professor Kastner's remark on retrocausality and lack of dynamics in the block universe is not accepted by other physicists like Richard Feynman, Yakir Aharonov, Lev Vaidman, Rod Sutherland, Huw Price, Ken Wharton and many others.
  19. Jul 1, 2016 #18
    To Dr. Highcastle: Richard Feynman is regrettably dead, so he has not taken any position on my statement. As for the others, perhaps they don't like it, since it apparently undermines their interpretation, but they haven't refuted it. So the point stands. I gave a talk on this at the recent AAAS conference on retrocausation in San Diego (see attached), and there was no refutation provided at that time, just some unhappiness. I do recall one questioner trying to argue that dynamical things are going on in a static spacetime, but clearly this is self-contradictory. Lack of acceptance of an argument or proposal does not equal refutation of the argument or proposal. Ernst Mach did not accept Boltzmann's atomic hypothesis either, but it turned out to be correct. Best wishes, RK

    Attached Files:

    Last edited: Jul 1, 2016
  20. Jul 1, 2016 #19
  21. Jul 1, 2016 #20
    Dear Professor Kastner
    I was referring to Feynman's classic papers on QED where he calls the block universe th "bird's eye view" if I recall correctly?
    Ken Wharton says you are using Humean causality when it is interventionist causality that allows dynamics in the block world which is part of Einstein's relativity.
  22. Jul 1, 2016 #21
    You misunderstand my point then. As I noted in the attached paper, there could be a block world, but if so, there is no dynamical retrocausation involved. (In any case, you can't say Feynman disagrees with me if he's never heard my arguments or proposals.)
    I am not alone on this; the Relational Block World authors (Mark Stuckey, Michael Silberstein, and their collaborators) agree that the block world is acausal and adynamical.
    I offer a different interpretation in which one does not need to take an 'observer' as primitively 'moving through' the block world. However I don't rule out a block world; I'm simply pointing out that it is inconsistent to claim there is any dynamical causation in a block world.
    Ken Wharton is not engaging with my argument. We went through this at the AAAS conference and I showed that there is no dynamics when one tries to apply "interventionist causality" -- so that does not solve this issue. I address this in the above attached paper as well. There can be no real 'causal interventionism' in a block world. This is trying to have it both ways. Agents and their actions are part of the block world, so there is no authentic "intervention." See the previously attached paper for detailed arguments.
    Last edited: Jul 1, 2016
  23. Jul 1, 2016 #22
    I do not agree. Dynamics is the 3D view of the observer's experiences. The 4D view is timeless.
  24. Jul 1, 2016 #23
    That would be a fine interpretation except that the researchers I'm discussing are invoking retrocausation within spacetime as a putative explanation for occurrence of other events in spacetime. This can't be just the perspectival dynamics of an observer moving through spacetime. Have you read my attached paper? I think that will clarify the issues in play here. Without benefit of that background I don't think we'll accomplish much going back and forth in messages on this board. Best wishes, RK
  25. Aug 5, 2016 #24
    Regarding the Transactional Interpretation, for those who are interested I just posted an overview and discussion of 'where we are now' with TI here: http://arxiv.org/abs/1608.00660
  26. Aug 6, 2016 #25


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