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

Recent Examples on the Web

Other solutions to the black hole information paradox include a way for infalling objects to radiate away data, or for information to somehow remain at the event horizon. Steve Nadis, Discover Magazine, "We've Found Gravitational Waves. What Will We Learn From Them?," 24 May 2019 The event horizon is left behind as an archaeological record while the stellar material continues to fall inward to an unknown fate. Quanta Magazine, "What the Sight of a Black Hole Means to a Black Hole Physicist," 10 Apr. 2019 But this is the first time an event horizon has been imaged directly. John Wenz, Popular Mechanics, "We've Seen a Black Hole Directly for the First Time," 10 Apr. 2019 Just a vast perfect nothingness known as the event horizon. Steff Yotka, Vogue, "Just Wait Until Fashion Designers Get Their Hands on This Black Hole Picture," 10 Apr. 2019 And while a picture of the black hole itself is impossible, the EHT astronomers were really aiming at the next best thing: the event horizon, the border of the black hole beyond which not even light can escape. Avery Thompson, Popular Mechanics, "We Might Be About to See the First Ever Photo of a Black Hole," 1 Apr. 2019 The event horizon is the edge of the black hole, the boundary beyond which nothing can escape, even light. Brian Resnick, Vox, "How a star orbiting a supermassive black hole proves Einstein is (still) right about gravity," 26 July 2018 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

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

29 Jun 2019

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The first known use of event horizon was in 1956

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