Hawking Radiation

Discussion in 'Physics & Math' started by The God, Mar 10, 2017.

  1. RJBeery Natural Philosopher Valued Senior Member

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    Well done, exchemist, sciforums really fell apart for a while and it's fantastic to see efforts to keep it an intellectual playground.
     
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  3. The God Valued Senior Member

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    No I am not being patronizing. Since you admit that its a difficult topic, indeed it is and it is very difficult to pass on the exact mechanism through pop science articles. The pop science description of HR is far from the real description and hence I asked to go a little beyond that. You just jumped the gun.

    Even in pop science scenario, the particle and anti particle are on this side of horizon and anti particle with negative energy falls inside the EH. Ideally the particle and anti particle should annihilate, but in this case particle escapes this side and negative energy of anti particle reduces the BH mass. I do not see any extraction from inside. Do you?


    The idea, you being a chemist will get it easily, information means entropy and entropy means temperature. So thermodynamics says anything with temperature must radiate, but BH by definition cannot. So Hawking attempted this HR theory mixing quantum mechanical effects near EH. As I said it has many issues and not many physicist endorse it, but then rpenner feels otherwise.
     
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  5. The God Valued Senior Member

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    Your insistence that something gets exported from inside of EH is, I am sorry, profound ignorance. What surprises me that you have an essay up for discussion on the topic without first umderstandimg this basic aspect on HR.

    PS: I feel bad that I am using bad words, because after exodus of paddoboy, even I want this place to have better and stimulating science discussions, some what above amateur level.
     
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  7. RJBeery Natural Philosopher Valued Senior Member

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    It's OK, it sounds like English is not your primary language so perhaps you don't have the ability to say things in a more diplomatic way. I have a fairly thick skin, too.

    Your mention of anti-particles was already discussed; what is the mechanism that preferentially sends the anti-particle through the EH?
     
  8. karenmansker HSIRI Banned

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    A comment: Lest we travel too far down the Scientific Method trajectory . . . . I'd refer to the HR Theory as the HR Hypothesis, or have we "observed" HR and are we able to test that hypothesis?
     
  9. The God Valued Senior Member

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    No I need not use diplomacy here. And from where you learnt that only native English people can write diplomatically? Another profound ignorance about others linguistic abilities.

    There is no mechanism which grants preferential treatment to anti particle, its probabilistic, just the QM effect for you.
     
  10. The God Valued Senior Member

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    No observation as such, but yes some analog tests are being done. Pl refer to Dumb Holes.... Sound counter part of Black Holes. Loosely speaking.
     
  11. exchemist Valued Senior Member

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    OK thanks for indicating you do not mean to be rude. I honestly feel the level of debate has improved immeasurably since his departure. We are all calmer and not at one another's throats the whole time.

    But please, try not to speak in terms such as "profound ignorance" if you want to conduct a civil discussion in English. (I cannot believe it is polite to do this in any language.) We all tend to think we understand better than the other guy, but the best thing is to show it, by the power of the points you make in argument, rather than saying so explicitly. This approach has the added benefit of leaving one a graceful exit when one screws up - which we all do from time to time.

    Back to the topic, though, I see your explanation is that antiparticles, from pair production, are preferentially sucked in by the black hole and cancel out some of the matter within. I do not find that satisfying, for 3 reasons:-

    1) I have not seen a mechanism to account for why antiparticles would be selectively drawn in (this is also Beery's question). Can you explain that?

    2) If this were what happened, then surely energy would be released when these antiparticles annihilated on encountering matter inside the BH? That energy would be equivalent in mass to that of the annihilated particles/antiparticles (E=mc²) and so the mass/energy of the BH would not decrease.

    3) The explanation I have now found, which I described in post 12, is a different one that does not suffer from these problems.

    I do not claim to understand this entirely. If you can explain how the problems in 1 and 2 are dealt with, in your conception of the HR process, then I would be very grateful.
     
  12. karenmansker HSIRI Banned

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    " . . . what is the mechanism that preferentially sends the anti-particle through the EH"

    allow me to suggest, again, 'spin' . . . . individual, differential intrinsic 'spin' (of each) of the particle-antiparticle pair - for simplicity, one goes 'left'. one goes 'right' . . . . thus one of the pair is ejected/repelled at the EH, the other is attracted/captured. (HSIRI)
     
  13. The God Valued Senior Member

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    There will be no energy release outside if an anti particle with negative energy gets sucked in. The mass of BH will go down, giving an impression that BH is evaporating.
     
  14. The God Valued Senior Member

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    I visited your #12

    So this export from inside of EH comes from stackexchange. No, please note nothing is exported from inside of EH.
     
  15. exchemist Valued Senior Member

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    OK but can you please do what I asked you, which is to explain to me, and to Beery, how your understanding of the process overcomes the difficulties I described in my 1 and 2?

    If you can do that I shall be happy. I only indicated the stack exchange explanation because it seems to overcome these 2 difficulties. I'm an outsider, so I have no dog in the fight either way.

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    Over to you...........
     
  16. RJBeery Natural Philosopher Valued Senior Member

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    Hi karen, spin in itself does not resolve the problem. The issue at hand is that, in order for anti-particles to carry negative energy into the black hole for that black hole to lose energy over time, then MORE anti-particles would have to cross the event horizon than their pair-production partners. The God is claiming that it's a matter of probabilities but, barring some mechanism, the probability remains at 50% for each.
     
  17. karenmansker HSIRI Banned

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    RJB: OK, thanks! . . . . but, indulge me for a moment with this analogy . . . . Suppose two oppositely-charged 'particles' (particle 1 - +; particle 2 = -) interact with a magnetic field. What would an 'observer' observe? Perhaps one particle turning left, whereas the other would turn right (without arguing the polarity of the magnetic field, for simplicity).

    Similarly for a virtual particle pair (VPs; particle and antiparticle) at the EH of the BH . . . . one VP would 'turn left' (say away from the EH and the BH accelerating btw) and the other would 'turn right', toward the EH (and accelerate into the BH). If not, can you explain (the simpler-the-better) what would actually occur. Thanks . . . . just curious . . . NOT trolling! (HSIRI)
     
  18. RJBeery Natural Philosopher Valued Senior Member

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    I'm not qualified to answer because the solution doesn't speak to me. If you're talking literally about spin (or something like it) and literally about physically turning toward and away from the BH then why would anti-particles in the pair-production be more or less likely to be spinning in a particular way or facing a particular direction than their partners?
     
  19. karenmansker HSIRI Banned

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    O: It has much to do with being a virtual 'pair' and the phenomenon of 'non-locality'. Is it not a reasonable conclusion that, when virtual pairs (particle and anti-particle) are 'formed' (however formed) as a 'pair', one of the pair exhibits properties and characteristics that are the 'opposite' (i.e., anti) of the other? The non-locality comes in when one 'measures' properties of one such pair-particle, the properties of the other are consequentially fixed. I may be in error on this, but perhaps you, or another SFIP (SciForums Interested Party), could elaborate to my benefit. Thanks!
     
  20. RJBeery Natural Philosopher Valued Senior Member

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    I guess if we wanted to get really speculative we could say that an anti-particle might react to gravity in a different way but...the "opposite" in this case would mean a repulsion away from the EH.
     
  21. karenmansker HSIRI Banned

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    Thanks RJB. I guess that I am using the term 'anti' in the traditional usage of others . . . . it infers that all properties and characteristics are exactly "opposite" in the pair, which may NOT be the case. 'Almost opposite' might be a more tongue-in-cheek representation, that could allow for slight property asymmetries or speculations that could help achieve the hypothesized BH effect. (HSIRI)
     
  22. The God Valued Senior Member

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    I think I have already answered both the questions in previous post. But over to the actual 1975 paper...

    You can get the paper here....https://www.brainmaster.com/software/pubs/physics/Hawking Particle Creation.pdf

    Please refer to page #4 onwards, I am giving a brief extract which answers your questions as well as touches upon RJB essay issue too..

     
  23. RJBeery Natural Philosopher Valued Senior Member

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    The God, do you feel comfortable with this description or are you just pointing to the material and expecting us to do so? In my opinion the original paper does not address our question.
    Hawking says the anti-particle is able to tunnel through the event horizon but offers no reason why quantum tunneling would be available preferentially to anti-particles over particles.
     

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