SpaceRock

Black holes are densely packed stars which are formed after a star’s life ends – typically by supernova or hypernova. The boundary of a black hole is called the event horizon. Beyond this boundary lies the singularity, a point of infinite density. Not even light can escape past the event horizon. Black holes originally were only theoretical, hypothesised due to Einstein’s field equations, but later supported by evidence until the first visuals captured on April 10, 2019, of the black hole  galaxy M87(it’s shadow) captured by Event Horizon Telescope(EHT).

Hawking radiation and quantum physics:-

• Quantum Field Theory states that our universe is not a perfect vacuum but actually a partial vacuum.
• Tiny fluctuations happen everywhere – normal matter particle and an anti matter particle come into existence and at that particular moment annihilate each other, preserving energy and quantum conservation laws.These pairs of particles are called virtual particles.
• One important part of quantum mechanisms is that Information in our universe can’t be lost.

Main Theory:-

• When these fluctuations happen near event horizon – One of the particle in the virtual pair may end in the black hole while the other one in the pair gets ejected. Also, the ejected particle is predicted to be observed as thermal radiation.
• Now since the ejected particle is new, and contains no new information of the other particle, the particle which falls into the black hole actually decreases the mass of the black hole. • This process decreases the mass of black hole little by little.
• And after 10^60 or more years the black hole  could have completely ‘evaporated’.