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Is time dilation a form of dimensional compactification?

As a probe approaches a black hole, toward a point on the equator of the event horizon, does general relativity predict that the time dimension is compactified like the extra dimensions of string theory? Will this compactification continue until the uncertainty principle becomes significant?

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    $\begingroup$ What do you mean by time getting compactified near a black hole? Compactification means to get a finite size. $\endgroup$ Commented Jul 21, 2013 at 12:47

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Is time dilation a form of dimensional compactification?

As far as I know, no, it isn't. Compactified dimensions have a finite extent, and as used in string theory they're typically periodic. For example, the Earth's surface has two compactified dimensions: you can't travel more than a certain distance in any one direction in that two-dimensional surface without returning to where you started. But that's not true of the time dimension, which is generally considered to be infinite. There is a sense in which time ends at a black hole singularity, much like the set of negative numbers ends at zero, but still, it extends infinitely far back in the other direction, and infinitely far forward outside the black hole.

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  • $\begingroup$ "you can't travel more than a certain distance in any that two-dimensional surface without returning to where you started" -> you might wanna clarify that you travel along a great circle. Because otherwise the statement doesn't hold. $\endgroup$
    – Marek
    Commented Aug 2, 2011 at 6:34
  • $\begingroup$ Ah, I didn't think to make that explicit... I'll change it. $\endgroup$
    – David Z
    Commented Aug 2, 2011 at 8:42

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