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If time is like space, why entropy always increases with time

I should not be able to distinguish whether I am going forwards or backwards in time.

As entropy always increase with time. I can distinguish past from future in a four dimensional space-time.


It looks like, it is an unresolved problem http://youtu.be/9VFGuupXwng There are some solutions http://youtu.be/RwYcPra40CY but nothing generally acceptable


marked as duplicate by ACuriousMind, user36790, Gert, Kyle Kanos, Bill N Nov 18 '15 at 19:50

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  • 2
    $\begingroup$ who said that time is like space? they may be treated "together" in a geometric object called spacetime, but they do not behave in the same way (for example, you can stay still in space, but not in time) $\endgroup$ – yuggib Nov 18 '15 at 12:11
  • $\begingroup$ Entropy is not an universal clock de jure ... it grows so-so like the time and some wonder if it is the clock ... not obvious answer without some beliefs $\endgroup$ – user46925 Jan 10 '16 at 10:19
  1. Time is not like space. It is a coordinate, as the space coordinates, but that doesn't mean it is the same.

  2. Read Ben Crowell's answer here. Entropy is stochastic, it doesn't have to increase monotonously. The very low current universe entropy can make the illusion that it always does, but there is still a very low probability that it decreases for a short time.


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