event horizon


Definition of event horizon 

: the surface of a black hole : the boundary of a black hole beyond which nothing can escape from within it

Examples of event horizon in a Sentence

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Hawking suggested that perhaps the event horizon is not some definite point of no return beyond which nothing could escape a black hole. Jennifer Ouellette, Ars Technica, "Stephen Hawking’s final paper published, tackles famous paradox," 11 Oct. 2018 Conceived and developed across the past two decades, in part to sidestep such conundrums, models of black stars and gravastars postulate these objects would lack singularities and event horizons. Charles Q. Choi, Scientific American, "Black Hole Pretenders Could Really Be Bizarre Quantum Stars," 16 Mar. 2018 In April 2017, astronomers collaborated using telescopes around the world to take a picture of the event horizon of the supermassive black hole. Brian Resnick, Vox, "How a star orbiting a supermassive black hole proves Einstein is (still) right about gravity," 26 July 2018 One of the main features of black holes is the event horizon, a region of space-time beyond which nothing can escape, not even light. Marcus Woo, Scientific American, "Gravitational “Echoes” Could Reveal Colliding Wormholes," 19 June 2018 But because any information that goes into a black hole is gone for good, an event horizon doesn’t jibe with quantum mechanics. Marcus Woo, Scientific American, "Gravitational “Echoes” Could Reveal Colliding Wormholes," 19 June 2018 Which means the guy not only knows about event horizons and gravitational lensing but stuff like tidal forces (what!), x-ray binaries (hey now!), and active galactic nuclei (oh my god!). Robbie Gonzalez, WIRED, "An Astronomer Explains Black Holes at 5 Levels of Difficulty," 5 July 2018 The gasses falling into the black hole experience high amounts of energy and glow brightly around the event horizon. David Grossman, Popular Mechanics, "The Fastest-Growing Black Hole Could Swallow the Sun in Two Days," 16 May 2018 At the event horizon, Hawking realized in 1974, one particle in a pair can fall into the black hole while the other escapes. Adrian Cho, Science | AAAS, "Hawking’s final quest: saving quantum theory from black holes," 20 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'event horizon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of event horizon

1956, in the meaning defined above

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Last Updated

30 Nov 2018

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The first known use of event horizon was in 1956

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to make faulty or ineffective

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