On 8 January 2014 11:06, meekerdb <[email protected]> wrote: > > If the universe reached a maximum and started to contract (which now seems > unlikely) the maximum possible entropy would still be much higher than the > actual entropy so entropy would continue to increase until the contracted > enough to reduce the maximum to near the actual. If it were the reverse of > the Big Bang it would be a very sudden contraction, aka "deflation". Of > course it might actually be symmetric. Lawrence Schulman has a nice book > about this "Times Arrow and Quantum Measurement". He did some computer > simulations by just considering randomized initial conditions and then > post-selecting the ones that satisfied the final conditions. >
We actually don't know what would happen in a "bouncing universe", or even if such a thing is physically possible. Certainly my mental image is that entropy would continue to increase, at least until it was approaching the Big Crunch, which would itself look something like a Big Bang in reverse (but with black holes thrown in). But if the BC acts as a boundary condition on the universe, as the BB appears to do, then that *could*constrain matter to follow an opposite arrow of time, no matter how anti-intuitive that seems - or there could be a gradual switch over from one arrow to another. Actually I once tried to write a story to this effect, with dark stars sucking in light and time-reversed aliens trying to flip their entropy gradient so they could avoid their BC, aka our BB. But I couldn't make it work very well, and gave up... -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
