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Alternative Ways of Decreasing Entropy in CCC

  1. Mar 31, 2015 #1
    Note: This is a question on a particular cosmological scheme, mainly Conformal Cyclic Cosmology.

    In Cycles of Time, Penrose says that Black Hole Information Loss causes the entropy to decrease in a way that doesn't violate the 2nd law. I think his analysis is correct, IF it was the case that information is destroyed. But that's not the case, or at least the vast majority of the quantum gravity community doesn't think it is. So, my question is, what other things could nature do in order to make the (gravitational, as Penrose puts it) entropy decrease?
    Penrose seems to have in mind some alternatives, mainly
    --> "there volume of the phase space is infinite (i. e. there is no a maximum entropy state)".
    --> "gravitational degrees of freedom 'scale away' " (I don't know what he means by that)
    I have thought of other crazy ideas, mainly:
    --> In an infinite time, some poincaré recurrance ought to happen in a finite time, and that would be the initial state of the next aeon. This doesn't satisfy me, because altough it could happen, one would have to choose a particular entropy value for the start of the next aeon, and that seems too arbitrary.
    --> The other option would be proposing that (gravitational) entropy is NOT conformally invariant, and its value significantly decreases in the "squash down" that Penrose proposes. I would be pleased if someone could clarify me the viability of this proposal.
  2. jcsd
  3. Apr 5, 2015 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
  4. Apr 6, 2015 #3
    I have been reading Cycles Of Time.

    Had to go back and scan through it. He talks in depth about a lot, at least that's how I found it. Honestly I need to reread it. I'm not really qualified to answer your question, but I thought it was a good one.

    My cartoon of the "scale away" was that in a universe with positive curvature, which I have recently been trying to conceptually de tangle from expansion, the infinite future is like a black hole horizon, and so total entropy of our phase space (as a region or point bounded by that) does something a lot bigger, meaning in some weird sense that the entropy of any point or region of the horizon remains, relatively tiny, or in some sense quasi-constant. I barely could follow it. There was (in COT) also what sounded to me like a really similar idea of the fabric of spacetime being a foam of black holes, so same kindof deal there. One big black hole at the distant future edge. Or a fabric of black holes inside everything. For my part the latter seems more interesting.. seems like a lot has happened, is happening on the LQG (Loop Quantum Gravity) front, since Penrose wrote COT.

    To me your proposal re non-conformal g DOF, sound kindof like his discussion of "phase space reduction" - which to me sounded like information destruction. That said, although I try to avoid I do keep coming back to the idea that information of some kind seems to be "going somewhere else" and/or (seems hard to distinguish) "coming from somewhere else". Maybe the phrase "non-conformal g DOF" is like this. Bulk-brane concepts I know have been talked about in the context of string theory, which as I understand it, is closely related to candidate QG theories.

    Good luck. Hopefully someone will shed more light for us both here.
    Last edited: Apr 6, 2015
  5. Apr 6, 2015 #4
    It's a bit fringe at this point. We can limit the selection bias by 1) Assigning a slight finite deviation before shifting to the next aeon -- and so on until it peaks and repeats again. 2) At the critical PR random field assigns the value of the consecutive aeons. 3) Combination of 1 and 2.. 4) Cycles of antimatter/matter universe... Heck! i'll stop here.
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