Schwarzschild radius

American  

[shvahrts-shilt, shwawrts-chahyld, -shild] / ˈʃvɑrtsˌʃɪlt, ˈʃwɔrtsˌtʃaɪld, -ʃɪld /

noun

Astronomy.

1. the radius at which a gravitationally collapsing celestial body becomes a black hole.

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Schwarzschild radius British  

/ ˈʃvartsʃɪlt, ˈʃwɔːtsˌʃɪld /

noun

1. astronomy the radius of a sphere ( Schwarzschild sphere ) surrounding a non-rotating uncharged black hole, from within which no information can escape because of gravitational forces

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Schwarzschild radius Scientific  

/ shwôrts′chīld′,shvärts′shĭld /

1. A radius defined for a body of a given mass and proportional to that mass, such that if the body is smaller than that radius, the force of gravity is strong enough to prevent matter and energy to escape from within that radius. The Earth is much larger than its Schwarzschild radius, which is approximately 7 mm (0.28 inches). Black holes are examples of objects smaller than their Schwarzschild radius, which defines the radius of their event horizon. The Schwarzschild radius is a consequence of Einstein's General Relativity theory. It is named after the German astronomer Karl Schwarzschild (1873–1916).

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Etymology

Origin of Schwarzschild radius

1955–60; named after Karl Schwarzchild (1873–1916), German astronomer

Example Sentences

What is the size of its Schwarzschild radius?

From Textbooks • Oct. 13, 2016

The surface surrounding a black hole, where the escape velocity equals the speed of light, is called the event horizon, and the radius of the surface is called the Schwarzschild radius.

From Textbooks • Oct. 13, 2016

One strange feature of his work was that at a certain distance from the star — to be known forever as the Schwarzschild radius — the equations would go kerblooey.

From New York Times • Nov. 24, 2015

The event horizon, the point beyond which light cannot escape, is now formally called the Schwarzschild radius.

From The Guardian • Dec. 12, 2012

This so-called Schwarzschild radius, or event horizon, is in effect the black hole's boundary.

From Time Magazine Archive