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The time dilation factor with respect to an observer at infinity is $$\sqrt{1-\frac{\text{2 G M}}{\text{c}^2\text{ r}}}$$ so if we plug in G=1, c=1, r=10 and M=+1 we get the clocks running slower by a factor of 0.8944 if they are in a distance of 10GM/c² from the center of the positive mass. If we change the sign of M to M=-1 we get a time dilation factor ...


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The arrow of time is believed to be related to the fact that the universe started in a state of low entropy and is evolving towards a state of larger entropy. The effect of negative mass will not change this. The reason is that any model of negative mass will leave the initial state of the universe as as state of low entropy. A rather uniform distribution of ...


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Here are some references: Time and chance by david Albert Time's arrow by huw price From eternity to here by sean carroll The direction of time by H. D. Zeh Physical basis of time Asymmetry by paul davies There are many other excellent books or articles about the subject. Especially, in relation to the foundation of statistical mechanics I saw Two ...


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As you and others have said, it looks like Boltzmann could plausibly be credited with the idea that the universe had a low-entropy past: The second law will be explained mechanically by means of assumption A (which is of course unprovable) that the universe, considered as a mechanical system—or at least a very large part of it which surrounds us—...


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Leaving aside the issue of wavefunction collapse, physics is deterministic. So if you have some system like a gas and you know the exact positions and velocities of all the gas molecules you can predict the evolution of the system forwards and backwards in time. So you can start with a future state and work backwards to desciribe a past state. However ...


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So that narrows it down to some time between 1896 and 1979 The second law was known to Clausius, and trivially implies the knowledge that the entropy in the far past was much less than now. (That is, if one is permitted to apply the notion to the universe as a whole; cf. below.) It seems that Clausius stated explicitly (in 1856) only the extrapolation to ...



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