Monday 5 September 2016

spacetime - Time paradox inside a black hole


At the event horizon of a black hole, time and the spatial direction toward the center exchange places. The direction inside the black hole from the event horizon to the the singularity in the center is the direction in time.


Assume a symmetrical non-rotating black hole and also assume that things can actually fall to the black hole. Consider that over 10 billion years a number of relatively small objects fall in. Finally, at the end, a number of larger objects also fall in that are big enough to increase the size of the event horizon.


Now let's look what's happening inside. The distance from the event horizon to the center is a time coordinate. Therefore, inside a symmetrical black hole, does the sphere of the event horizon represent the same moment of time? If so, then all things that have been falling in over 10 billion years appear all at once on the inside at the same moment that the sphere of the event horizon represents. Is this correct?


Finally, when the larger objects fall in and increase the size of the event horizon, on the inside, a larger radius would represent an earlier time than a smaller radius. Correct? If so, the larger things that fell in at the very end appear on the inside before everything else that's been falling in over 10 billion years. Is this the proper understanding?


In fact, if a black hole has been growing over time gradually increasing in size by sucking the external matter in, on the inside this process would appear happening in reverse, because time inside goes from a larger to smaller radius of the event horizon. Is this correct?



And if it is, then would this not violate causality? For example, consider that a large asteroid was supposed to fall in at the very end, but got hit by another asteroid and both avoided being sucked into the black hole. However, on the inside, this asteroid falls in "before" everything else and therefore is already there when everything else falls in.




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