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Hawking Radiation paradox

  1. Oct 16, 2013 #1
    Hi all, to begin this is my understanding of hawking radiation. A particle/anti-particle pair is generated. one particle outside the event horizon of a black hole, the other inside. The gravitational force "boosts" the one particle into being real. this energy is compensated for by endowing negative energy to the one particle-evaporating the black hole. my question is what if a pair is produced within the event horizon and the pair is separated due to the tidal forces of the black hole? Thanks in advance, sorry if I was not clear enough.
     
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  3. Oct 16, 2013 #2

    Bill_K

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    What happens in black holes stays in black holes.
     
  4. Oct 16, 2013 #3

    phinds

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    No, as I understand it, the pair is created OUTSIDE the EH and one falls in.

    Actually that whole discussion is moot anyway since the "virtual particle" description of Hawking Radiation has been described by Hawking as an overly simplistic / unrealistic way of looking at what his math describes.
     
  5. Oct 16, 2013 #4
    but im saying if the pair is produced inside a black hole and becomes real there due to tidal forces wouldn't the negative energy just destroy information?
     
  6. Oct 17, 2013 #5

    phinds

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    Huh? WHAT information?
     
  7. Oct 17, 2013 #6

    Drakkith

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    It was my understanding that if the pair is produced inside the black hole, then they will not become "real". The only way to become "real" is for one to be created outside the event horizon and to escape. I could be wrong.
     
  8. Oct 17, 2013 #7
    Why doesn't hawking radiation solve the black hole information paradox?
     
    Last edited: Oct 17, 2013
  9. Oct 17, 2013 #8

    phinds

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    What does that have to do with your question about a virtual particle pair forming INSIDE the EH?

    hawking Radiation is often described (inaccurately) using an analogy of virtual pairs being formed OUTSIDE the EH but inside and outside are WAY different
     
  10. Oct 17, 2013 #9
    The point of this thread was for me to try understand information conservation inside black holes and why hawking radiation doesn't solve black hole information paradox
     
  11. Oct 17, 2013 #10

    phinds

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    Aha ... well, that would have been more clear if your original post, or even the subject line, had had the word "information" in there somewhere. I thought you were just asking about the MECHANISM of Hawking radiation which is why I answered the way I did.

    Lenard Suskind and Stephen Hawking had a 20-year battle over whether or not information was lost when matter enters a black hole. Hawking said yes, Suskind said no. Suskind finally won by saying that the information about the particles entering the BH was somehow contained in a hologram at the EH and that it was released back into the universe via Hawking Radiation as the BH evaporates over a huge amount of time.

    I do not understand at all how the information is contained in a hologram at the EH, but that seems to be accepted theory. You can find a lot more on the Internet than I'm able to tell you. Maybe you'll get lucky and someone here will do your research for you and explain it all.
     
  12. Oct 17, 2013 #11

    Drakkith

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    Because the emitted particles don't give you any information on what fell into the black hole, so you've still lost information.
     
  13. Oct 17, 2013 #12
    I suggest you talk about "inside the event horizon" and "outside the event horizon".

    If you dropped into a black hole, you would not be impressed with the event horizon at all. Chances are you would be destroyed before you reached it or you would pass through it without noticing. So it's not synonymous with "black hole".

    On the other hand, from outside the black hole, the event horizon is as far as you can see. Anything approaching the black hole will asymptotically approach a moment in time when time freezes. Nothing that happens on the other side of the horizon has any obvious bearing on the outside world.

    Hawking Radiation, a feature of event horizons, was once described as purely random - created by particle pairs splitting just above the horizon with one of the pair managing to escape while the other dropped back to the horizon. Now it is most often described as not entirely random. Instead, the event horizon is plastered with the blended time-frozen holograms of everything that has ever dropped through the horizon and it is this holographic surface that is involved in "deciding" what particle pair evaporation takes place. So it's not random - just inscrutably complex.

    As for whether there really are any particle pairs, there probably is a better way to describe it, but it's good enough for me.

    Event horizons are not specific to black holes. If you accelerate continuously in one direction, you will leave an event horizon in your wake - although it may be trailing you at quite some distance. That event horizon will have the same properties as the black hole event horizon. So at this very moment, you are probably passing through the event horizon from the perspective of some accelerating particle somewhere in this universe.
     
  14. Oct 17, 2013 #13

    phinds

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    Oh Oh ... Leonard Susskind is going to smack you so hard !
     
  15. Oct 17, 2013 #14

    Drakkith

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    I was unaware that he had won the argument. My mistake.
     
  16. Oct 17, 2013 #15

    phinds

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    Oh, he didn't just WIN it, he shoved it in Hawking's face and wrote a book about their war and how he won it. All in the best of fun, of course.
     
  17. Oct 17, 2013 #16
    Firstly thanks all for the help. Secondly what was the name of the book?
     
  18. Oct 17, 2013 #17
    "The Black Hole War"
    Hawking conceded in July 2004.
     
  19. Oct 17, 2013 #18

    phinds

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    Actually, it was more fun than that:

    The Black Hole War: My Battle with Stephen Hawking to Make the World Safe for Quantum Mechanics
     
  20. Oct 18, 2013 #19

    Demystifier

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    Because Hawking radiation CREATES the black hole information paradox. Without Hawking radiation, there would be no information paradox at all.
     
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