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white hole
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Tweet n. A hypothetical spacetime singularity similar to a black hole except that matter and energy are emitted rather than absorbed at the event horizon. Though theoretically possible according to general relativity, the existence of isolated white holes is generally considered to be physically impossible because they would violate the second law of thermodynamics, which prohibits the spontaneous reversal of many natural processes. [WHITE + (BLACK) HOLE.] |
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