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Questions about black holes

  1. Apr 19, 2012 #1
    I want to clarify some stuff about black holes and have some questions:

    1) From the perspective of a hovering near the event horizon observer an external universe evolve at very fast rate. But from the perspective of a free falling observer an external universe slows down. Correct?
    2) If (1) is correct, the next question is Why actually the free faller would see an external universe slowing down?
    3) The falling observer would never see what is inside a black hole since light can’t escape it. So all he could be able to see in front is contracting “black spot” all the way towards singularity. Am I correct?
    4) Is light from all of objects that fell into a black hole stored on its event horizon? So the falling observer would see instantaneously all these objects at the EH?

    Hope someone can clarify it for me.
  2. jcsd
  3. Apr 19, 2012 #2
    1) I believe this is correct.
    2) The best clock there is, is light and whether it is red shifted or blue shifted. The hovering observer would see light gaining energy as it approaches the event horizon so it would be blue shifted. A free falling observer however would see objects behind him seem to move farther and farther behind him*. The light reflected off objects that appear to be moving away from him would be red shifted.

    * If you drop two objects one after the other, to each object, the other will appear to be moving away from it because the first object is already moving away when the second object is released.

    3) and 4) I will leave to others.
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