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Ger. /shvahrddts"shilt'/; Eng. /shwawrts"chuyld', -shild/, Astron.
the radius at which a gravitationally collapsing celestial body becomes a black hole.
[1955-60; named after Karl Schwarzchild (1873-1916), German astronomer]

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Radius inside which the gravitational attraction between a body's particles must cause its irreversible gravitational collapse, named for Karl Schwarzschild.

This is thought to be the final fate of the most massive stars (see black hole). The gravitational radius (Rg) of an object of mass M is given by Rg = 2GM/c2, where G is the universal gravitational constant and c the speed of light. For a star like the Sun, the Schwarzschild radius would be about 1.8 mi (3 km).

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the radius below which the gravitational attraction between the particles of a body must cause it to undergo irreversible gravitational collapse. This phenomenon is thought to be the final fate of the more massive stars (see black hole).

The Schwarzschild radius (Rg) of an object of mass M is given by the following formula, in which G is the universal gravitational constant and c is the speed of light: Rg = 2GM/c2.

For a mass as small as a human being, the Schwarzschild radius is of the order of 10-23 cm, much smaller than the nucleus of an atom; for a typical star such as the Sun, it is about 3 km (2 miles).

The Schwarzschild radius is named for the German astronomer and physicist Karl Schwarzschild (Schwarzschild, Karl), who investigated the concept in the early 20th century.

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Universalium. 2010.

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