CitationsAdd new citationList by: CiterankMap Link[1] Time's Arrow and Eddington's Challenge (article)
Author: Huw Price - Director, Center for Time, University of Sydney Cited by: Peter Baldwin 5:35 AM 6 May 2011 GMT Citerank: (6) 100641The Arrow of Time?A map exploring some issues concerning the nature of time that lie at the boundary of physics and philosophy. The map follows up a talk to the Blackheath Philosophy Forum on 2 April 2011 by Huw Price, Professor of Philosophy and director of the Center for Time at Sydney University.7F1CEB7, 103810Why do we see an entropy gradient?We find ourselves in an observable universe in which entropy increases consistently in one direction, thereby showing time asymmetry - an arrow of time. Yet the vast majority of underlying dynamical processes are time-symmetric. How to account for this? Two broad approaches are considered here.8FFB597, 103810Why do we see an entropy gradient?We find ourselves in an observable universe in which entropy increases consistently in one direction, thereby showing time asymmetry - an arrow of time. Yet the vast majority of underlying dynamical processes are time-symmetric. How to account for this? Two broad approaches are considered here.8FFB597, 104152Past hypothesisWe inhabit a universe - or part thereof - characterized by a low-entropy past that has enabled the evolution of intelligent observers to occur. This together with Boltzmann's probabilistic argument (see sibling node) implies entropy will increase over time toward thermal equilibrium.109FDEF6, 104155Boltzmann-Schuetz hypothesisBoltzmann and Schuetz claimed that in a universe that is near thermal equilibrium, and given sufficient time, there will be regions where there is a temporary deviation into a low entropy state, from which it will trend back to equilibrium. Anthropic selection accounts for us being in such a region.959C6EF, 105365Anti-matter objectionIf the time-asymmetry of thermodynamics were associated with the symmetry violation of the neutral K meson (neutral Kaon) then anti-matter would show the reverse of the normal thermodynamic asymmetry AND no such anti-matter reversal is apparent.13EF597B URL: | Excerpt / Summary "In particular, I think it is helpful to distinguish three distinct elements in dynamic conception. These elements tend to be bundled together, but in principle they can be separated, and defended in almost any combination. (We already encountered two of them in Section 2, when we considered what Eddington has in mind when he discusses `time's arrow'.)
1. The view that the present moment is objectively distinguished, and that reality is objectively divided into past, present and future. 2. The view that time has an objective direction that it is an objective matter which of two non-simultaneous events is the earlier and which the later. 3. The view that there is something objectively flow-like" about time that time - really "goes on", as Eddington puts it.
Philosophers who defend the Block Universe picture tend to be steadfast in their rejection of (1) and (3), and a little bit more open minded about (2). In physics, however, it easy to find famous critics of all three elements." |
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