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How is it that black holes are black?

  1. Apr 24, 2009 #1
    It is generally accepted that light cannot escape a "black" hole because the singularity's gravitational pull is too strong for photons (or waves, or wavicles, or whatever) to achieve movement away from the singularity.

    Isn't gravity a warping of space? And isn't space a facet of a single phenomenon called space-time?

    Could it be that: Since light propagates at a finite velocity -- which means distance per unit time -- there is a certain volume around the singularity where space-time is stretched to the point where there is no time, or insufficient time, for light to escape -- or to escape as electromagnetic energy?

    Maybe time in the region is of a nature that the light has not had time, or time yet, to escape. Maybe 2.7 billion years from now, light will finally begin to leak from some older "black holes." Perhaps it will emerge not as light, but as some other energy/matter. Think of a vast slow glass.
  2. jcsd
  3. Apr 24, 2009 #2


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    It's generally said that the escape velocity of the black hole is greater than c, meaning not even light can escape, that's why they're black and we don't see them...
  4. Apr 24, 2009 #3
    Here is a best picture I've seen.
    It explains everything.

    Attached Files:

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