Hawking radiation

Discussion in 'Physics & Math' started by hardalee, Sep 16, 2015.

  1. brucep Valued Senior Member

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    It's beyond his purview. The basic difference between Newton's model 'action at a distance' and Einstein's local model of gravity. Much easier to understand Einstein's model. At least for me.
     
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  3. OnlyMe Valued Senior Member

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    Above you take my comments from the earlier thread out of context, the first sentence of the post you quoted was,
    The rest was an extension from that.

    What I have believed about the significance of GR has evolved and even changed over the years, largely as I have struggled to try and understand something of the theoretical work, involving quantum gravity and even inertia from a perspective of field theory... but that is a wholly different discussion.

    The idea that you appear to maintain is what I have called a modern interpretation of GR and leads to the idea that spacetime itself, is the source of gravitation rather than just a geometric field description of the dynamics we can observe. And it does so without describing how, as if all should just bow down and accept it.

    In that context it seems from my perspective that it is you that forgets that spacetime geometry is a model. A model that describes what we observe, rather than the cause of what we observe.

    But this is not really the topic of discussion in this thread, and not even the side track that began when I asked Bruce for clarification about his use of the word "fact", as it relates to Hawking radiation, how many pages back now? If this is an important issue for you, go ahead and quote my post in the original thread and restart some discussion there. It doesn't serve any constructive purpose here.
     
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  5. paddoboy Valued Senior Member

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    Very short GRBs may be Hawking radiation source:


    Very short gamma-ray bursts (VSGRBs) last less than 0.1 second and have been detected by several GRB instruments including the BATSE experiment on the Compton Gamma Ray Observatory, the KONUS experiment, and NASA's Swift gamma-ray burst mission.

    The evaporation of primordial black holes was postulated as a possible high-energy source for GRBs as a whole, but these events do not in general fit the characteristics of such an event. Hawking, in collaboration with Bernard Carr, proposed that the evaporation of black holes left over from the early universe would produce a burst of energy; GRBs in general are too bright and too uniformly spread over the sky to have come from primordial black holes.

    Now David B Cline and colleagues from the University of California in Los Angeles argue that these VSGRBs are a distinct population that does fit the characteristics of primordial black hole evaporation, notably their anisotropic distribution in the sky and lack of significant afterglows. Cline presented these results to the GRB2010 meeting in November.

    http://www.physics.ucla.edu/hep/vsgrb/vsgrb_ichep2010.pdf


    • A particular group of gamma-ray bursts, those of very short duration, have characteristics that suggest they may be the signature of an evaporating primordial black hole — the Hawking radiation proposed by Stephen Hawking in 1974.
      ____________________________________________
    I did mention this earlier in the piece. Worth considering?
     
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  7. BrianHarwarespecialist We shall Ionize!i Registered Senior Member

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    Beware Krash661 maybe silent but you will stand to gain from his insights if you can follow his subtle contributions here and elsewhere on the net. I have noticed it just goes over the heads of most...

    There will come a time when mankind will no longer waste intellectual resources on fruitless arguments, because the very design of our existence is based on small isolated parts working together to create a grand unification.

    We are much like nanites...
     
  8. paddoboy Valued Senior Member

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    Both sides in this debate have slandered and been less than respectful shall we say.
    But you should also realise that some that come here have a reputation that in general rejects mainstream science, and yet they still put their alternative positions as fact within the mainstream sciences section.
    Nothing wrong with that per se, but we also have the alternative sections for that. That can and does create some angst.
    Then we have the same alternative people that in essence are no more than trolls that suffer with delusions of grandeur, and go out to purposely deride science and the giants of science, present and past.
    It would be nice without slander and name calling, but in a forum of this nature, open to any Tom Tom Dick and Harry, that will not happen.
     
  9. The God Valued Senior Member

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    This guy must be the only person here, who has understood the distrotion in the curvature of the spacetime and ripples in the spacetime (whatever) ? I bet if any one can write in words for lay to understand what these two ghosts are. GR has become a behemoth, an inertial behemoth, will require substantial efforts to dislodge.

    The fact which is being completely overlooked is that GR is a single body soultion and moreover why we resort to Newtonian almost everywhere if the premises of both the theories are different ?
     
  10. sweetpea Valued Senior Member

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    After reading this...
    It seemed to me you where taking models literally... see my post on that other thread.
     
  11. BrianHarwarespecialist We shall Ionize!i Registered Senior Member

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    Keep on posting Barry the goal is not to make others agree with you but give information. Some individuals may be beyond or behind the information, but the benefits will always be of a subjective nature. I for one believe you have posted many interesting articles. Some speculative but sometimes you can't get away with not speculating, in fact after directly taking notes on empirical facts we can document them as behaviour of phenomenons but our descriptions of those things will always remain subjective speculations.
     
  12. paddoboy Valued Senior Member

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    26,404

    While being open to speculative scenarios, and admitting making plenty myself, I do believe that I always try and separate the speculative scenarios from the accepted scientific theories, and make that as clear as possible.
    That appears to be the problem of late....Some cannot distinguish between speculative stuff and evidenced backed scientific theories.
    Having hyper-inflated egos and agendas, certainly does not help in that distinguishing aspect.
     
  13. tashja Registered Senior Member

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    Thank you, guys, for your kind words. I love to read your feedback whenever I post a Prof's. reply. I liked that comment by Brucep about how the Profs approached HR from different angles. It seems there are more ways than one to skin HR.

    Q -- I hope you keep asking uncomfortable questions. You may not always get the answers you want, but it's very educational to participate in debates with logical people that pose informed, challenging, and dissenting POVs. That is why I enjoy RJBeery's threads as much as I enjoy your questions.

    I asked Prof. Susskind that very question, Paddo:

     
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  14. paddoboy Valued Senior Member

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    They are totally deserved and thanks again.
     
  15. brucep Valued Senior Member

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    This is a revealing discussion about the string landscape. One of my favorites authored by Professor Susskind. Worth reading if your interested in the path to quantum gravity and the theoretical obstacles encountered.
    http://arxiv.org/abs/hep-th/0302219
     
  16. Daecon Kiwi fruit Valued Senior Member

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    I suspect that Tashja is secretly the alias of a famous celebrity scientist who wishes to remain anonymous.
     
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  17. brucep Valued Senior Member

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    We, humans, discovered the scientific method to make theoretical predictions and experimental results as objective as possible. The subjective bullshit is the domain of pseudoscience.
     
  18. brucep Valued Senior Member

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    That's just an excuse for overlooking the inaccuracy of terminology used by some lay folk participating in a science forum. It's hard to do once you understand how important the correct terminology is to any science discussion.
     
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  19. BrianHarwarespecialist We shall Ionize!i Registered Senior Member

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    This what you have said is the obvious, you seemingly have missed my point...
     
  20. brucep Valued Senior Member

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    I know what you said and if it's so obvious to you why did you use 'subjective speculation'. You don't say that and I don't say anything to you. Since the discussion is about science then I'm going to interpret comments literally.
     
  21. BrianHarwarespecialist We shall Ionize!i Registered Senior Member

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    I said everyone will benefit from the objective information in a subjective way which is logically a correct statement.

    Then I also stated any attemp to describe objective empiral facts will by default make those descriptions subjective.

    Hope this was more clear...
     
    Last edited: Oct 12, 2015
  22. brucep Valued Senior Member

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    That may be logical to you but "objective information in a subjective way" is pretty much gibberish to me. No problem. It's perfectly clear to you.
     
  23. BrianHarwarespecialist We shall Ionize!i Registered Senior Member

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    Any documentation of objective facts is never the exact facts themselves, they are at best approximations unless you intend to violate the uncertainty principle. Further all interpretation has a variating degree of freedom with the statistical error margin of measuring capabilities which in turn would classify all measurements as approximations and approximations or not exact facts but subjective interpretations. Hence this is why the scientific method is based on a falsifiable principle if scientist were 100 percent certain there descriptions of phenomenons was completely deterministic then there would be no need to falsify them.
     

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