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Blackholes theory maybe incorrect?

  1. Jul 28, 2006 #1
    Blackholes theory maybe incorrect??


    source: http://www.newscientistspace.com/article.ns?id=dn9620&feedId=online-news_rss20 [Broken]
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Jul 28, 2006 #2
    But i like Black Holes

    i can understand where there coming from
    good story
  4. Jul 28, 2006 #3


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    But, that site/article also says that:
    which hasn't been accepted as the case,AFAIK. We went through this on PF many months (years?) ago and an old Labguy post was:
    So, unless all of these boys are incorrect, it shouldn't be a surprise that any and all BH's have a magnetic field.

    Some of the above quote are from other quotes and I have added the bold and underline emphasis. I have saved this to my own computer as a Word.doc so I would have to do a lot of searching to get to all the original material....Too lazy...:biggrin:
  5. Jul 28, 2006 #4
    When black holes rotate, don't they "drag" the reference frame with them, giving it a kind of rotation? Wouldn't virtual particles of the vacuum be dragged with the reference frame. And if the charges are separated by the horizon, then won't there be circulating charges and the magnetic field associated with it?
  6. Jul 28, 2006 #5


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    Not sure what you mean by "circulating charges", but frame dragging is an important contributor of the field generation, which is why the above big quote specifically mentions Kerr BH's (rotating). Virtual particles would have angular momentum, but when escaping the energy required is provided by angular momentum and the magnetic fields.

    http://relativity.livingreviews.org/open?pubNo=lrr-2003-7&page=articlesu21.html [Broken]
    Last edited by a moderator: May 2, 2017
  7. Jul 29, 2006 #6
    I'm no expert by any means. I'm just trying to understand these things in terms of puemonics that are easy to intuitively understand. By frame dragging I assume there is a component of acceleration tangent to the horizon surface in the direction of rotation. And I also assume that accelerating in the tangential direction means there is a higher velocity of the virtual particles of the vacuum tangent to the horizon when compared to more distant vacuum away from the black hole. Then when the virtual charges are separated due to the horizon, the acceleration tangent to the horizon amounts to a circulation of these charges which causes a magnetic field that separates the charges even more. Does this sound correct?
  8. Jul 29, 2006 #7
    speaking of rotating- from what i have gleaned on the subject it seems to me that Schwarzschild black holes could be unphysical- as they could only be formed by a non-rotating mass with a perfectly symmetrical collapse into a singularity- is this correct?

    from this it seems to me since virtually all stars have some rotation and a collapse would amplify the rotation- that the only physical black hole would be more like Kerr rotating black holes with the inner cauchy horizon-inversion to 'normal' spacetime inside and no singularity but the missable neutronium ring at the center with possible Eintein-Rosen bridge inside the ring where the singularity would be-

    is that right? as I understand it ANY rotation leads to the Kerr metric- not the Schwarzschild solution
    Last edited: Jul 29, 2006
  9. Jul 29, 2006 #8


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    My very long quote in the 3rd post has in it:
    so no, there are not likely any non-rotating BH's.

    The "Kerr BH" is thought to have the "ring singularity" of zero volume (I believe there is no zero volume and no infinite density) and I haven't yet heard of the "neutronium ring at the center with possible Eintein-Rosen bridge", even though some might speculate (ad infinitum).
    Yes, but the difference in velocity would be due to both the BH's angular momentum and the effect of frame dragging. Those "other VP pairs" created away from the BH have no specific reference frame from which to judge velocity; they are just "there and then not there".
    A seperation "due to the horizon" is a discussion of classic Hawking Radiation (HR) where one of the pair escapes and one doesn't. This leads to Wheeler's 3rd "no-hair" property of charge. But, I am talking about non-HR where two virtual particles are created and both can escape. As in the long quote I posted above, the energy for the creation of both pairs comes from the magnetic field(s) only. The energy that might allow both to escape comes from the BH's angular momentum.
  10. Jul 29, 2006 #9


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    Your references seem to be talking about magnetic fields associated with the Hawking process, which would have a completely negligible impact on the quasar light. The paper in the OP is claiming to observe magnetic fields of much greater strength in the inner regions of the accretion disk.

    As for the MECO article, I wouldn't get too worked up about it. Their analysis rests on a lot of assumptions that are hard to verify. Quasars are extremely difficult to unravel because there are so many things going on in the vicinity of the SMBH. I suspect we won't see any definitive test of this model until we can directly image the accretion disk around a black hole (and even then, I'm not sure). It's worth noting that similar arguments have been made that support the existence of an event horizon (at least in stellar mass black holes):

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  11. Jul 29, 2006 #10


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    True, as far as the three new references listed, but we got on the subject of magnetic fields around a BH in response #4 and #6. Plus the OP quote from the article had said:
    and I was just showing that all BH's would have magnetic fields; nothing about powering Quasars or Hawking radiation. That part is the reference that:
  12. Aug 11, 2006 #11
    There's another paper on MECO up on arxiv in case anyone misses it: http://arxiv.org/PS_cache/astro-ph/pdf/0608/0608178.pdf [Broken]
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