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Q& A: Black Holes
Q:
How does a black hole consume matter? What happens to the matter
it consumes?
A:
Matter is consumed by a black hole when the gravitational force
of the black hole pulls it beyond the event horizon, from which
the matter cannot escape because the gravity is too strong. The
ultimate fate of the matter is unknown since nothing, not even
light, can escape from inside the event horizon and give us
information about what happened to the material. The theory
indicates that it must be crushed to an extremely high density
-- to a point at which the theory no longer applies! However,
since nothing can escape from a black hole, all energy and mass
of the matter is captured inside of the black hole. According to
the theory, this energy and mass is not destroyed, though it may
change forms. Since energy is equivalent to mass in Einstein's
theory of relativity, the mass of the black hole increases
slightly.