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Did abhas mitra proved that black holes dont exist

  1. May 16, 2005 #1
    u can get his proof by mailing me or just quote on it whether he had really proved and did hawking accept it
     
  2. jcsd
  3. May 16, 2005 #2

    wolram

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    WHAT is this?
     
  4. May 16, 2005 #3

    wolram

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    A goggle found this papper.

    http://arxiv.org/abs/astro-ph/0407501

    Authors: Abhas Mitra (NRL, BARC, India)
    Comments: Thoroughly revised, new eqs. new ref., new supporting proof, many points clarified, physical interpretation included

    It is believed that the basic component of the central engine of quasars, micro-quasars, and energetic Gamma Ray Bursts are the rotating or the Kerr Black Holes (BH)[1]. But by using a generic property[2-4] of the metric components of a stationary axisymmertic rotating metric in its standard form}, namely, g_phi \phi = sin^2 theta g_theta theta, where phi is the azimuth angle and theta is the polar angle measured from the axis of symmetry, we have found the unexpected and surprising result that (i) in order to have a mass of a Kerr BH m ge 0, it is necessary that its rotation parameter a=0 and if one insists for an a ge 0, one must have m le 0! Thus if the suspected Black Hole candidates with m >0 are really rotating they cannot be BHs at all which is in agreement with some detailed analysis of recent observations[5-8]. However, if it is assumed that such objects are strictly non-rotating, they could be non-rotating Schwarzschild BHs (a=0) with m ge 0 if we ignore the physical difficulties associated with the existence of such objects. This result calls for new theoretical efforts to understand a vast range of astrophysical phenomenon. If one derives the Kerr Metric in a straightforward manner by using the Backlund transformation, it is seen that a=m sin phi. This relationship confirms that a=m=0 for Kerr BHs.
     
  5. May 16, 2005 #4

    wolram

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    And this

    http://o3.indiatimes.com/contradiction/archive/2004/08/03/559.aspx


    Black holes and white mans burden

    This is the story of a man who took on Stephen Hawking, one of the greatest living scientists in the world. Hawking had decades ago proposed the black hole theory, which said that when stars collapsed under the pull of their own gravity, they destroyed matter that fell on them. So a black hole could actually have light fall on it and make that light disappear, instead of reflecting or refracting. This naturally gave rise to massive possibilities both in science and science fiction.

    Scientist Abhas Mitra, some four years ago, said that this theory was incorrect, since it violated Einstein's theory of relativity (don't ask me how). Anyway, after having said this, Mitra was ostracized by his colleagues at the Bhaba Atomic Research Centre for daring to challenge Hawking. Mitra tried to get criticism of his theory from eminent astrophysicist Jayant Narlikar and even Hawking himself, but got no response. BARC moved him out of his department on some silly excuse. His colleagues ignored him.

    Now, Hawking admitted a couple of weeks back that black holes don't really gobble everything up. They keep emitting radiation for a long time.

    For a country (and media) that doesn't tire of talking about brain drain on the one hand and the native intellectual brilliance of its citizens on the other, we've done ONE fine job with Dr Mitra, haven't we? It might be too harsh for Contra Diction to say so, but it does look like the brown man still doesn't have the guts to take on the gora sahebs. And this was not the first incident. Subramanian Chandrashekhar's work was considered incorrect by a gora astrophysicist though no one could point out why. And this was in the 1930s. The more things change, the more they remain same?

    posted on Tuesday, August 03, 2004 10:24 AM
     
    Last edited: May 16, 2005
  6. May 16, 2005 #5
    I took a brief look at the paper and it seems like what Mitra is doing is assuming that if you use a rotating frame of reference to look at a rotating black hole then you should get a stationary black hole - his equation (6). From this assumption he derives a contradiction. If this were valid then it would not just show that black holes don't exist, it would also mean that General relativity was inconsistent. Thus I would deduce that such an assumtion is not valid.

    Of course this is not related to Hawking's recent pronouncement that information is preserved by black holes, which is based on quantum considerations. Personally I think that such quantum considerations will be taken to show the non-existence of black holes (see http://www.chronon.org/articles/blackholes.html) but this shouldn't be taken to support more general claims of their non-existence (see http://math.ucr.edu/home/baez/RelWWW/wrong.html#holes)
     
  7. May 16, 2005 #6

    selfAdjoint

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    By this logic if you looked at the rotating earth with a rotating frame of reference you would see a stationary earth. But this is what we do every day, in our lives, and it works only up to first order. You also have centripetal force and coriolis force that appear as uncaused forces in the rotating frame.
     
  8. May 16, 2005 #7
    True. It would be interesting to see whether Mitra's argument could be reframed in this setting. His argument seems to be that the rotation should only affect the metric components related to the plane of rotation (r, phi and t), and not the remaining one (phi). So centrifugal force would be OK, but possibly his argument would show that Coriolis force didn't exist. Alternatively it may just be the general relativistic predictions such as frame dragging that are affected.
     
  9. May 16, 2005 #8

    wolram

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    The papers that he quotes as supporting his work, i wonder if the
    magnetic propeller is more real than the event horizon.

    http://arxiv.org/abs/astro-ph/0402445
    Authors: Stanley L. Robertson, Darryl J. Leiter
    Comments: 6 pages, 1 figure. Accepted by MNRAS
    Journal-ref: Mon.Not.Roy.Astron.Soc. 350 (2004) 1391

    In previous work we found that the spectral state switch and other spectral properties of both neutron star (NS) and galactic black hole candidates (GBHC), in low mass x-ray binary systems could be explained by a magnetic propeller effect that requires an intrinsically magnetic central compact object. In later work we showed that intrinsically magnetic GBHC could be easily accommodated by general relativity in terms of magnetospheric eternally collapsing objects (MECO), with lifetimes greater than a Hubble time, and examined some of their spectral properties. In this work we show how a standard thin accretion disk and corona can interact with the central magnetic field in atoll class NS, and GBHC and active galactic nuclei (AGN) modeled as MECO, to produce jets that emit radio through infrared luminosity $L_R$ that is correlated with mass and x-ray luminosity as $L_R \propto M^{0.75 - 0.92}L_x^{2/3}$ up to a mass scale invariant cutoff at the low/high spectral state switch. Comparing the MECO-GBHC/AGN model to observations, we find that the correlation exponent, the mass scale invariant cutoff, and the radio luminosity ratios of AGN, GBHC and atoll class NS are correctly predicted, which strongly implies that GBHC and AGN have observable intrinsic magnetic moments and hence do not have event horizons.

    http://arxiv.org/abs/astro-ph/0102381

    Authors: Stanley L. Robertson, Darryl J. Leiter
    Comments: Submitted to ApJ, Feb. 22, 2001, minor errors corrected and introduction rewritten in present version. 8 pages
    Journal-ref: Astrophys.J. 565 (2002) 447-454

    We present evidence that the power law part of the quiescent x-ray emissions of neutron stars in low mass x-ray binaries is magnetospheric in origin. It can be very accurately calculated from known rates of spin and magnetic moments determined from the the $\sim 10^{3 - 4}$ times brighter luminosity at the transition to the hard spectral state. This strongly suggests that the spectral state transition for neutron stars is a magnetospheric propeller effect. We test the hypothesis that the similar spectral state switches and quiescent power law emissions of the black hole candidates might also be magnetospheric effects. In the process we derive proposed magnetic moments and rates of spin for them and accurately predict their quiescent luminosities. This constitutes an observational test for the physical realization of event horizons and suggests that they may not be formed during the gravitational collapse of ordinary matter.
     
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