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A General Relativity and Hawking Radiation at the Event Horizon

  1. Mar 31, 2016 #1
    The question is to resolve a logical conflict.

    GR says as we fall into a black hole, an outside observer will see that event come to a stand still as if the falling object is hovering at the horizon. This stand still extends to infinite time. Unfortunately, I've read and hear the term "infinite" time used to describe this through experiment from a number of respectable physicists. Assuming that is the correct term then it conflicts with another effect about black holes; the Hawkin radiation (HR). If HR predicts that the black hole eventually evaporates in finite amount of time, that must predict the falling object at some time disappears. The conflict is GR predicting infinite time while HR predicts finite time.

    While I'm not a Physics/Mathematician, I still think that these extreme conditions of the experiements should at least converge to the same logical result. What am I missing?
  2. jcsd
  3. Mar 31, 2016 #2


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    GR predicts infinite time, IF the BH were to stay as is. Clearly you are right in that when it evaporates, this no longer holds because you are talking about different conditions.
  4. Mar 31, 2016 #3


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  5. Mar 31, 2016 #4
    Aahha, of course. The "If stay as is" is the condition I overlooked. thanks.
  6. Mar 31, 2016 #5


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    I think you are expecting a lot from the current understanding of both GR and Quantum Theory. This is an extreme case in both theories where they meet.
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