User:Mpatel/sandbox/Black hole
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A black hole is a region of space where mass is so concentrated that nearby matter or electromagnetic radiation (such as visible light) cannot escape the overwhelming gravitational field. The event horizon of a black hole marks the 'point of no return', a boundary that, if crossed, inevitably leads falling matter and radiation towards the central singularity.
Several types of black hole are thought to exist, their existence being theoretically predicted to arise as solutions of Einstein's field equations of general relativity, the currently accepted theory of gravitation. Black holes are generally believed to form from the collapse of massive stars. Others are thought to arise from quantum mechanical processes in the early universe.
Quantum mechanics research also indicates that, rather than holding captured matter forever, black holes may slowly leak a form of thermal energy called Hawking radiation and may well have a finite life.[2][3][4] Together with white holes, black holes are speculated to form wormholes, shortcuts through space and time. The as yet unknown theory of quantum gravity is believed to give the fully correct description of black holes.
Black holes are believed to reveal their presence through interaction with orbiting material. Recent observations of orbiting stars and gas indicate evidence for black holes.[5][6] Such observations have resulted in the general scientific consensus that, barring a breakdown in our understanding of nature, black holes do exist in our universe.[7]