(Phys.org) —The quintessential feature of a black hole is its "point of no return," or what is more technically called its event horizon. When anything—a star, a particle, or wayward human—crosses this horizon, the black hole's massive gravity pulls it in with such force that it is impossible to escape. At least, this is what happens in traditional black hole models based on general relativity. In general, the existence of the event horizon is responsible for most of the strange phenomena associated with black holes.
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