
Quantum entanglement, two-sided spacetimes and the thermodynamic arrow of time - ovidiu69
https://arxiv.org/abs/1904.04012
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TomMckenny
Probably a basic question, but if entropy is causally connected to time, why
don't different locales have different rates of time based on how rapidly the
local environment is moving toward greater entropy.

That is, in deep space almost nothing is happening while here on earth a lot
is happening to increase entropy, so why does time go at the same speed in
both places?

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nopassrecover
It doesn’t - Special / General Relativity demonstrates gravitational time
dilation.

~~~
trypt
So you mean our simulation doesn't bother calculating the state of empty areas
on which there are few or no other dependent states which depend in a
statistically significant way upon that empty state?

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mikorym
Based on initial conditions, the two-sided spacetime behaves differently with
respect to the (thermodynamic) arrow of time.

If the initial conditions are of low correlation, the two sides move in
opposite time directions, but the structure as a whole follows the
thermodynamic arrow of time.

If the initial conditions are of high correlation, the individual entropies of
the two sides can increase and decrease, there is not a dominance over time
direction, and the overall structure is that of a one-sided spacetime.

So, their argument on the dual structure is:

less correlation = more disconnection between spacetime forming two-sided
geometry

more correlation = more connection, forming one-sided geometry

Remember, though, that we are looking at dual views: gravity vs. quantum
information theory and depending from which view you are describing, the words
used to describe the system would be different. For example, two-sidedness in
geometry refers to the gravity view.

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lisper
Another explanation for how time can be an emergent property of entanglement:

[http://blog.rongarret.info/2014/10/parallel-universes-and-
ar...](http://blog.rongarret.info/2014/10/parallel-universes-and-arrow-of-
time.html)

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ovidiu69
The point here is the universe has two sides; we can only observe one side. On
the other side of the universe the time runs backward, from the future to the
past. If one, by any chance, would traverse to the other side, will "grow"
younger.

