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B Kim et al, 1999 experiment and causality

  1. Dec 8, 2017 #26


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    It might be interesting for you to look at this (a bit emotional) post: https://www.physicsforums.com/threads/delayed-choice-quantum-eraser-again.885423/#post-5619033
    There is nothing new, but you can find out what other lay person took as intuitive explanation of this experiment.
  2. Dec 8, 2017 #27
  3. Dec 12, 2017 #28


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    You don't have to think of any 'thing' moving backwards in time when discussing retrocausality. The idea that present outcomes depend on future boundary conditions is probably best understood adynamically as a pattern in the block universe. That is, block universe explanation trumps time-evolved explanation, so while most phenomena accommodate time-evolved explanation, there are some phenomena better left to the more fundamental block universe explanation. Here is an Insight on retrocausality I wrote a couple years ago https://www.physicsforums.com/insights/retrocausality/. This followed a 5-part series entitled "Blockworld and Its Foundational Implications" that starts here https://www.physicsforums.com/insig...time-dilation-length-contraction/#toggle-id-1 . In that series you'll find many examples of the power of adynamical explanation. That series was the precursor for an entire book written on this subject for Oxford UP that is due out in Feb 2018 https://www.amazon.com/Beyond-Dynam...sr=8-1&keywords=beyond+the+dynamical+universe. My point is that viewed adynamically, retrocausality is perfectly reasonable -- we just have to give up our dynamical bias.
  4. Dec 13, 2017 #29
    Thanks a lot Ruta! I will look into that and post my impressions! I'm gonna start reading it right now!

    I've been watching some the Feymanns introductory lectures and I'm trying to understand the Schrodinger equation and I've got an idea, and I would like that my forum friends tell me if I'm in the right direction or the wrong one.

    Here it is, as the photon is fired, there is an equation that could have many limited numbers of solution. But there's no solution to that equation that the photons could reach detector 0 in the "particle only" spot and his entangled pair reach the "don't know which way" detector, so the photon simply doesn't do that.

    I say that because, as far as I know, Schrodingers equation allows many solution to a given quantum state, but many of that solutions has such a low odd of happening that it's irrelevant. Also, there are some impossible solutions, like the idler photon coming to Brazil and hitting my eye.

    Am I in the right path?

    Thanks! =)
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