Also according to the theory of relativity, nothing can travel faster than the speed of light but most compact objects imaginable are predicted by General Relativity to have such strong gravitational force that nothing can escape them- not even light. For this reason, it is called a black hole; light, as a result disappears from the visible universe. John Mitchell, an English geologist, had written a paper in 1783 about the extraordinary strength of gravity- so strong that light could not escape it. ...

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