At First,it Was Thought That Nothing Could Ever Escape from a Black

question 36

Multiple Choice

At first,it was thought that nothing could ever escape from a black hole,yet astronomers are now locating black hole candidates by the X-rays they emit.Do they really see X-rays coming from a black hole?

• A) The X-rays come from highly compressed matter in the accretion disk outside the event horizon of the black hole.
• B) The black hole modifies spacetime around it so much that particles and X-rays are created in the vacuum itself,just outside the event horizon.
• C) The X-rays are produced by vibrations of the black hole itself,and therefore they come from the event horizon,and not from inside the black hole.
• D) X-rays are neither light nor matter and therefore can escape from inside the black hole.

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1924 Immigration Act

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