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Singularity prevented by repulsive force?

  1. Jul 20, 2004 #1
    If hadrons carried a new kind of charge that exerted a significant
    force only over very short distances so that hadrons repel hadrons at
    close range,this force could stop the formation of a singularity when
    a massive star collapses. There is no evidence for the existence of
    such a force, but are there theoretical reasons for believing that
    there can be no more forces in nature?
  2. jcsd
  3. Jul 21, 2004 #2
    There are no theoretical reasons for believing there are no more forces in nature. But we don't postulate something unless we have experimental evidence for it; otherwise we could write down theories for infinitely many forces with any behavior we wanted.
    My knowledge of general relativity is much weaker than that of particle physics, but I don't think such a force can stop the collapse to a singularity. I think there is a theorem in GR that once some matter collapses inside its own Schwarzschild radius, no force, however strong, can stop its collapse towards the singularity. The space is curved to such a degree that all timelike paths lead towards the singularity so unless the particles move faster than light, they cannot escape.
  4. Jul 21, 2004 #3
    The space is curved to such a degree that all timelike paths lead towards the singularity

    Can dark energy oppose this curvature - it is gravitationally repulsive?
  5. Jul 21, 2004 #4


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    The strong force is repulsive at very short distances.

  6. Jul 21, 2004 #5
    My knowledge of GR is limited, as I've said. Try the astronomy or cosmology forums for this one.
  7. Jul 21, 2004 #6


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    I did not know this, but it makes more sense now. Does this refer to the direct or residual strong force. I thought that the strong force was an HO force at the smallest distances.
  8. Jul 21, 2004 #7


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    Pauli principle amounts to impenetrability for identical spin 1/2 particles. That is the main trick.

    On a related note, some famous problems actually bypass the singularity problem. Between them, I have read, the classical gravitational three body problem has a perturbative expansion that avoids the singularity in origin.
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