User:Mpatel/sandbox/White hole

A white hole is a theoretical celestial body that spews out matter. In Einstein's theory of general relativity, white holes are usually defined as the time reversal of black holes.

Scientific status
White holes have been postulated as a means of transport between points of spacetime and even different universes. Due to a black hole's suggested funnel-like nature, matter travelling through a black hole and exiting through a white hole would be crushed to an immensely dense but small size, which would go against transportation because it is very unlikely that a white hole would have the ability to recompose the matter to its original state prior to entering the black hole. This very process is sometimes regarded as meaningless as a black hole is actually a collapsed star and a white hole would presunmably be a star which ejects matter in the time-rversed manner of a black hole. The existence of white holes is hypothetical, as they appear to violate the second law of thermodynamics.

Other speculations include the hypothesis that quasars are actually white holes instead of supermassive black holes.

Relation to entropy
The existence of white holes is hypothetical, as they appear to violate the second law of thermodynamics.

White holes in science fiction
White holes have been used in science fiction.