The whole content of the cosmic black hole

In modern general relativity, a black hole is the celestial body with the largest density and the smallest volume in space. The gravity of a black hole is so great that the escape velocity in the event horizon is greater than the speed of light.

19 16, the German astronomer karl schwarzschild (1873 ~ 19 16) got the vacuum solution of Einstein's gravitational field equation through calculation. This solution shows that if a large amount of matter is concentrated at one point in space, strange phenomena will appear around it. That is, there is an interface around the particle-once the "horizon" enters this interface, even light cannot escape. This "incredible celestial body" was named "black hole" by American physicist john archibald wheeler.

A black hole is a celestial body in the curvature of spacetime. It is too big for light to escape from its horizon.

A black hole is a star with enough mass to collapse and die after the fuel of nuclear fusion reaction is exhausted. The mass of a black hole is extremely huge, but its volume is very small. The gravitational field generated by it is very strong. Any matter and radiation entering an event horizon (critical point) of the black hole can no longer escape, even the light (electromagnetic wave) with the fastest known propagation speed can't escape.

A black hole cannot be observed directly, but its existence and mass can be indirectly known, and its influence on other things can be observed. Information about the existence of black holes can be obtained by the "edge information" of gamma rays emitted by high heat before the object is inhaled. Inferring the existence of black holes can also be obtained by indirectly observing the orbits of stars or interstellar clouds and air masses.

The latest research theory of scientists shows that when a black hole dies, it may become a "white hole". It is not like a black hole devouring all the neighboring substances, but all the substances captured by the black hole before ejection.

Scientists speculate that passing through a black hole may reach another space, even spacetime.