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The points raised regarding entropy are good ones & very relevant to the quaestions of the "appearance" of time & it's "arrow" & the reality of motion. You quite rightly say that random fluctuations in a Universe in total thermal equilibrium could give no sense of time "progressing" to a "God-like" observer in a way that we would recognise. In fact a maximum entropy state can & according to quantum theory must, randomly decrease or reverse it's entropy at some point in "time" & space, so that to a local observer, time might even appear to run backwards?
This relates to the distinction between different "arrows of time" ie the entropic arrow & the psychological arrow & the corresponding distinction between "time as change" & "duration". Relating this to the idea of time as unique configurations, if an observer experienced the configurations in the reverse order, they may perceive time to be running backwards while still having the same sense of duration "advancing" in time. This assumes the conscious observer's brain processes are not somehow reversed also!
The example of maximum entropy also impacts on whether Barbour's static configurations can be maintained by his "action" principle? The principle would seem to lose the power to "best match" the configurations. It becomes a question then of whether the mechanism he uses to constrain the wave function amplitudes to "coincide" with the "time capsules" can determine random changes, particularly in the case of entropy decreasing changes?
Paul, you seem to be using the argument of causal violation via a sort of two-way "multiplication" of effects as being the reason we can't travel in time . I think that would certainly be a consequence of travel to a past "point" in a consistent causal history. I simply believe we can't access "previous" points or "past" events for similar reasons to Mr Smith, that is, that the particular configuration which defines the event(time) no longer exists. I feel that any object has a "trajectory" relative to all other objects, defined only by it's relative position & relative velocity. These continuous relative trajectories are what create our notions of local time, in the case of similar non-relativistic trajectories, or relative "time" differentials in the case of large velocity and/or vector separations.
Does any of that make sense?!