- #1
liometopum
- 127
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I am looking for some input on the proper use of the definition of the Schwarzschild radius.
Case 1: In the world of black holes, the Schwarzschild radius is used in reference to the distance from the center of a mass dense enough to not allow light to exit. It is a short distance compared to Case 2's value.
Case 2: Every point in space has a Schwarzschild sphere of points around it at a distance at which the accumulated expansion of space equals the speed of light. No mass is necessary. These points are presumably 13.8 billion light years away from the point, or earth, or whatever.
So, is it common, or proper, to use the term Schwarzschild distance, or radius, for case 2?
(the math definition does not seem to help. In Case 1, a large mass in the 2GM/c^2 equation gives a large radius. The tiny (or almost zero mass) in Case 2 gives a tiny radius.
Case 1: In the world of black holes, the Schwarzschild radius is used in reference to the distance from the center of a mass dense enough to not allow light to exit. It is a short distance compared to Case 2's value.
Case 2: Every point in space has a Schwarzschild sphere of points around it at a distance at which the accumulated expansion of space equals the speed of light. No mass is necessary. These points are presumably 13.8 billion light years away from the point, or earth, or whatever.
So, is it common, or proper, to use the term Schwarzschild distance, or radius, for case 2?
(the math definition does not seem to help. In Case 1, a large mass in the 2GM/c^2 equation gives a large radius. The tiny (or almost zero mass) in Case 2 gives a tiny radius.