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Subatomic Reversibility of Time?

  1. Nov 26, 2009 #1
    I'm posting as a music student (composer) who is interested in philosophy, particularly philosophies of time. Recently, I've my interests have tended towards the writings Fraser, Whitehead, Eddington, Russell and the like. I only mention this because responses to my question are only helpful if they assume a very weak mathematical background (like Russell's ABC of Relativity). . .

    I heard in a lecture recently that at the subatomic level certain particles (I think it might have been electrons and positrons. . . not sure) can interact in such a way that the interaction can be viewed as having happened both in forward and in reverse time, i.e. the "effect" is, or at least appears to be, produced prior to the "cause."

    I assume this is a generally accepted aspect of quantum theory? If accepted, what is the theory known as?

  2. jcsd
  3. Nov 26, 2009 #2
    The equations that describe the microscopic dynamics of matter is exactly identical in both time directions.

    But in the macroscopic world this is rarely the case. For instance, we are used to seeing a car starting to move, heating the road but we "know" it is impossible to observe road getting cold and car moving forward.

    It is very difficult to arrive at this "arrow of time" using microscopic theories, because from a pure dynamical point of view, there's no difference between the two examples.

    In physics, these two separate theories evolved independently (thermodynamics -- dynamics) and they were finally connected by L. Boltzmann.

    But the emergence of irreversibility is still an open-ended question in some ways, I still see a few PRL papers every now and then on the subject.

    You could check Ludwig Boltzmann and Boltzmann equation, emergence of irreversibility, etc...

    Edit : I play the piano (mostly classical Western) but Shostakovich is someone I cannot "survive" more than 10 minutes, I hope you don't get offended
    Last edited: Nov 26, 2009
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