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Colapse to singularity and Pauli principle.

  1. Nov 6, 2008 #1
    If a star is sufficiently massive, neither electron or neutron degeneracy pressure will stop it from forming a black hole.

    How is Pauli exclusion principle reconciled with collapse to a singularity ? Since no two neutrons can occupy the same quantum state at the same time, how comes a singularity exists ?
  2. jcsd
  3. Nov 6, 2008 #2

    Jonathan Scott

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    According to the "no hair" theorem, a singularity has no properties except mass, angular momentum and total electric charge, so once a particle has become part of it, it completely loses its original identity.

    I don't think you'll get a more specific answer in terms of quantum theory at the moment, as quantum theory and black holes don't go well together, and neither do quantum theory and gravity in general.
  4. Dec 13, 2008 #3
    How about if we relate black holes to the big bang theory?

    Quantum mechanics don't need to be ruled out. Hawking radiation is used to explain how black holes radiate their heat. Since the laws of conservation require a black hole to conserve their mass during collapse, black holes have an entropy that is proportional to the area contained with the horizon. Since heat radiation cannot escape it must evaporate in a different manner.

    Through a quantum mechanical process near the horizon the vacuum of space is no longer empty as defined by classical physics; this region is a place where "virtual particles" are constantly created and destroyed. Virtual particles form a particle-antiparticle pair that aids the evaporation process of a black hole. When they are forced to separate (Heisenberg Uncertainty principle applied), the particle is sent off into space while the anti-particle falls into the horizon.

    Anti-particles are negative matter that compensate for the ejected "normal matter" particle. As these negative matter particles enter the horizon they serve to decrease the overall mass of the black hole. Black hole temperatures are inversely proportional to their mass; the more mass radiated away, the hotter the black hole gets. Eventually the black hole reaches a temperature of several trillion K and explodes.

    These properties are all characteristic of the big bang theory. In the Planck era (10^-10< t <.001 sec) the temperature is said to have been ~ trillion K and during this time there was a constant process of the creation and destruction of virtual particles.

    Singularities also serve to curve space time infinitely around them in such a way that time does not exist. If the big bang marked the beginning of time then it is quite possible the event was a singularity in reverse. When gravity separated from the 4 unified forces it set forth a chain of events that led to the universe as we know it today.

    Following the creation of particles, the era of nucleosynthesis served to provide protons/ neutrons which were later combined in the era of nuclei and finally formed into atoms within the first billion years.

    So here's my position:
    The Pauli exclusion principle is violated when the force of gravity is strong enough. Incredibly dense objects provide this gravity; the fabric of space is unable to support the weight and curves the surrounding space time infinitely.

    Isaac Newton's laws can be applied to give weight to my argument.
    If the chain of events that created particles can be said to exist, the same process in reverse has the power to destroy them and possibly break them down into their original form. "For every action there is an equal and opposite reaction" so to speak.

    Unfortunately a black hole explosion has never been witnessed. Evaporation times of a black hole are proportional to the cube of their mass. The universe has not existed long enough for an ideally formed black hole to evaporate fully.

    What will happen when they explode?

    Please offer your criticism to my argument. Most of my reasoning is theoretical.
  5. Dec 13, 2008 #4


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    This is well outside of the realm where we can splice general relativity and quantum mechanics together -- answering such a question would require a coherent theory of quantum gravity, which we do not yet have.

    That said, it's fun to contemplate meaningless questions, and one meaningless answer is that, in GR, matter simply "falls off" the universe when it reaches the singularity. It's gone, kaput; there's nothing left of it but the echoes of its influence on the gravitational and other fields. And since the neutrons no longer exist, there is no longer a problem. :wink: (Of course, this raises other problems)
  6. Dec 14, 2008 #5
    What about the similarities in behavior that black holes/ big bang both exhibit. Are you completely ruling out the possibility that the universe came into existence by means of a "singularity in reverse?"
  7. Dec 15, 2008 #6
    What singularity?
  8. Jan 28, 2009 #7
    Keeping in mind that all stars rotate, is it possible that as a star collapses, the conservation of angular momentum insists that matter approaches the speed of light as it rotates closer to r=0 which causes the matter to break down. As it's commonly accepted that most of the neutron, protons mass is the gluon interaction between the quarks which might be described as having a lot in common with the photon in electromagnetism (spin=1, no mass) but with the exception of being able to carry colour charge, is it possible that particles are stripped of any material properties the closer they get to the BH centre and basically become a form of electromagnetism? The rate of spin would dictate at what radius this would occur which might have some baring on the properties of the ring singularity in rotating black holes (it also takes care of the Pauli exclusion principle).
    Last edited: Jan 28, 2009
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