A black hole is a cosmic body with a very high density and concentration of matter, that even light cannot escape from it, which is an incredible speed (300,000 km / s).
The presence of these objects affects their environment in extreme ways, such as the deformation of space-time.
The existence of black holes is assumed by Einstein’s theory of relativity. According to classical general relativity, no matter or information can flow from the inside of a black hole to the outside observer.
The existence of black holes in the universe is well supported by astronomical observations, mainly from the study of supernovae, X-rays from the active galactic nucleus, and the behavior of matter and the radiation around it.
On April 10, 2019, scientists from EHT (Event Horizon Telescope) succeeded
take a picture of a black hole M87.
A black hole is formed whenever a sufficient amount of matter condenses in a given space in space (most often during the gravitational collapse of a star with three times the mass of the Sun)
According to the General Theory of Relativity, a black hole can be characterized by the following 3 parameters: mass, angular momentum and electric charge.
Parts of the black hole:
The horizon of events called the surface of the black hole is the surface surrounding the black hole with an escape rate equal to light (300,000 km / s). Therefore, the extraordinary gravitational field prevents the escape of even a photon across the event horizon. Objects in the gravitational field are subject to a slowing of time, called time dilation.
As expected, there is a singularity in the center of the black hole, a place with infinite curvature of space-time and infinite gravitational force. All particles in the space beyond the event horizon move towards the singularity.
In 1975, Stephen Hawking applied the theory of the quantum field to the curved space-time around the event horizon and found that black holes could radiate the so-called Hawking radiation, which results in the loss of weight of a black hole and the subsequent evaporation of a black hole.
Despite these incredible findings, to this day we do not know exactly what is inside the black hole, and unfortunately we will probably never find out.