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B Black holes and time

  1. Jan 8, 2017 #1
    I'm not a physicist so Im very igorant on this subject. From I know time gets slower and slower as you approach a black hole and an outside observer would never actually see matter being gobbled up. But I have read about stars get observed getting eaten away. How is this possible? And how do black holes move? If time essentially stops in one how do we observe it move in space?
  2. jcsd
  3. Jan 8, 2017 #2


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    You are experiencing a very common misconception brought about by poor (and even fallacious) descriptions in pop-sci presentations.

    No, it does not. It just looks that way to a distant observer.

    The matter being eaten appears to slow down as it approaches the Event Horizon but we see it headed that way and infer correctly that despite how it looks to us, it is in fact falling into the Event Horizon.

    just like everything else in the unverse moves.
    Since time does NOT slow down, there's no issue.
  4. Jan 8, 2017 #3
    Might I ask whether its true that matter or energy falling into a black hole always leaves information on the event horizon?

    (Talk about Big Brother surveillance...)
  5. Jan 8, 2017 #4


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    That's what Leonard Susskind believes and finally convinced Stephen Hawking of (Google "The Holographic Principle"). Personally, I just don't get the holographic principle at all but I do concede that those guys know more than I do.

    Susskind wrote a book about it "The Black Hole War: My Battle with Stephen Hawking to Make the World Safe for Quantum Mechanics"
  6. Jan 8, 2017 #5
    Thank you, I'm a little familiar. If I beleive an electron can be everywhere at once I'm at the mercy of experts from there on lol
  7. Jan 8, 2017 #6


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    Yes, but an electron can NOT be everywhere at once. That's another pop-sci fallacy. It can be ANYWHERE until measured, but that's a far cry from being everywhere at once.
  8. Jan 8, 2017 #7
    Thanks I hadn't planned to mention it, you get a lot thrown in when googling for research.
  9. Jan 8, 2017 #8
    If electrons really are everywhere at once I urgently need better reading glasses.
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