On 1 December 2014 at 14:48, <[email protected]> wrote: > On Thursday, November 27, 2014 7:22:19 PM UTC, [email protected] wrote: >> >> On Thursday, November 27, 2014 8:16:40 AM UTC, Bruce wrote: >>> >>> LizR wrote: >>> > On 27 November 2014 at 04:51, spudboy100 via Everything List >>> > <[email protected] >>> > <mailto:[email protected]>> wrote: >>> > >>> > Entropy and Time seem related, or at least one seems at least one >>> > aspect of the other. Is it sensible to think then, that there are >>> > two or more types of entropy, therefore, there are at least two >>> > dimensions of time? >>> > >>> > Entropy is a large scale statistical effect (classically) and has no >>> > direct bearing on time. If it can be made more fundamental then >>> perhaps, >>> > yes... >>> >>> Entropy has a direct bearing on the direction of time via the second law >>> of thermodynamics. "The second law of thermodynamics states that in a >>> natural thermodynamic process, there is an increase in the sum of the >>> entropies of the participating systems." (Wikipedia). Increase is a >>> temporal statement. One could not state this law without reference to >>> the passage of time. The 'increasing' part gives the direction of time. >>> >> This only works because the system is constrained to be in a low entropy state in the past, possibly due to boundary conditions. If a system was constrained by the laws of physics to be in a low entropy state in the future the AOT would be reversed for that system. (This is partly suggested by what happened to matter falling into black holes, which is physically unable to do certain things, such as escape.)
None of this is built into physics, however. The laws of physics are time symmetric (apart from CPT violation in neutral kaon decay and possibly gravitational collapse, although quantum theory suggests that will prove not to be the case for a system described by quantum gravity). I am only talking about fundamental physics when I say that entropy has no bearing on time. Obviously it has a contingent bearing on it, apparently due to the way the universe happens to be structured.. -- 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/d/optout.
