Answer:

White hole is a hypothetical region of spacetime and singularity which cannot be entered from the outside, although energy-matter and light can escape from it. In this sense, it is the reverse of a black hole, which can be entered only from the outside and from which energy-matter and light cannot escape. White holes appear in the theory of eternal black holes.

Answer:

In general relativity, a white hole is a hypothetical region of spacetime and singularity which cannot be entered from the outside, although energy-matter, light and information can escape from it.

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