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event horizon

event horizon Boundary of a black hole, from which nothing can escape. Observers outside the event horizon can therefore obtain no information about the black hole's interior. The radius of the event horizon is called the Schwarzschild radius. At the event horizon, the escape velocity equals the velocity of light with the consequence that all electromagnetic radiation is trapped. Its presence can only be detected by its powerful gravitational force.

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event horizon

e·vent ho·ri·zon • n. Astron. a theoretical boundary around a black hole beyond which no light or other radiation can escape. ∎  fig. any point of no return: we're nearing the event horizon of the presidential election.

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"event horizon." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. 24 Feb. 2018 <http://www.encyclopedia.com>.

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