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Black hole radiation

  1. Jul 9, 2012 #1
    Why is it generally acccepted that light can't escape from a black hole when gamma and radio wave radiation has been shown to be coming from them? A way I can think around this is that the expulsion happens before the event horizon and is some sort of rejection phenomenon that fuels a chain reaction. Sorry if that's crossing more into theory. Anybody got answers?
  2. jcsd
  3. Jul 9, 2012 #2


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    Gold Member

    Yes, you are correct that the expulsion happens OUTSIDE the EH. NOTHING escapes from inside the EH.

    Even Hawking Radiation, which is sometimes misunderstood as being something that radiates from inside the EH, does NOT involve anything coming OUT of the EH, but rather a negative energy dropping into the EH while an equivalent positive energy moves further away from the EH.
  4. Jul 9, 2012 #3


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    Staff: Mentor

    What Phinds said, plus you have to remember that accretion disks get very very hot, ionized, and emit lots of radiation when the matter is in the process of falling into the BH, but before it passes the event horizon.
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