Schwarzschild metric

In <a href="/facts/Albert_Einstein/CNTet8qu">Einstein</a>'s theory of <a href="/facts/General_relativity/jVsoIg8X">general relativity</a>, the Schwarzschild metric (also known as the Schwarzschild solution) is an exact solution to the <a href="/facts/Einstein_field_equations/j2rJTzW9">Einstein field equations</a> that describes the <a href="/facts/Gravitational_field/K1uTmJFy">gravitational field</a> outside a spherical mass, on the assumption that the <a href="/facts/Electric_charge/xxsBfmlB">electric charge</a> of the mass, <a href="/facts/Angular_momentum/7TuSVFxq">angular momentum</a> of the mass, and universal <a href="/facts/Cosmological_constant/bjMksSA2">cosmological constant</a> are all zero. The solution is a useful approximation for describing slowly rotating astronomical objects such as many <a href="/facts/Star/PFbd6ICx">stars</a> and <a href="/facts/Planet/rbPjE6Bx">planets</a>, including Earth and the Sun. It was found by <a href="/facts/Karl_Schwarzschild/u9KGeTey">Karl Schwarzschild</a> in 1916.
According to <a href="/facts/Birkhoff%27s_theorem_(relativity)/L8nj5T3F">Birkhoff's theorem</a>, the Schwarzschild metric is the most general <a href="/facts/Rotational_symmetry/bpvJqcnS">spherically symmetric</a> <a href="/facts/Vacuum_solution_(general_relativity)/M8BSxN4x">vacuum solution</a> of the Einstein field equations. A Schwarzschild black hole or static black hole is a <a href="/facts/Black_hole/1r2lmkcF">black hole</a> that has neither electric charge nor angular momentum (non-rotating). A Schwarzschild black hole is described by the Schwarzschild metric, and cannot be distinguished from any other Schwarzschild black hole except by its mass.
The Schwarzschild black hole is characterized by a surrounding spherical boundary, called the <a href="/facts/Event_horizon/KXH2ptnI">event horizon</a>, which is situated at the <a href="/facts/Schwarzschild_radius/jINV5oxD">Schwarzschild radius</a> (
 
 
 
 
 r
 
 s
 
 
 
 
 {\displaystyle r_{\text{s}}}
 
), often called the radius of a black hole. The boundary is not a physical surface, and a person who fell through the event horizon (before being torn apart by tidal forces) would not notice any physical surface at that position; it is a mathematical surface which is significant in determining the black hole's properties. Any non-rotating and non-charged mass that is smaller than its Schwarzschild radius forms a black hole. The solution of the Einstein field equations is valid for any mass M, so in principle (within the theory of general relativity) a Schwarzschild black hole of any mass could exist if conditions became sufficiently favorable to allow for its formation.
In the vicinity of a Schwarzschild black hole, space curves so much that even light rays are deflected, and very nearby light can be deflected so much that it travels several times around the black hole.

Schwarzschild metric open-in-new

Schwarzschild metric