Singularity prevented by repulsive force?

  • Thread starter kurious
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  • #1
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Main Question or Discussion Point

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?
 

Answers and Replies

  • #2
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kurious said:
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?
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.
 
  • #3
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Zefram:
The space is curved to such a degree that all timelike paths lead towards the singularity

Kurious:
Can dark energy oppose this curvature - it is gravitationally repulsive?
 
  • #4
Njorl
Science Advisor
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kurious said:
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?
The strong force is repulsive at very short distances.

Njorl
 
  • #5
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kurious said:
Can dark energy oppose this curvature - it is gravitationally repulsive?
My knowledge of GR is limited, as I've said. Try the astronomy or cosmology forums for this one.
 
  • #6
turin
Homework Helper
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Njorl said:
The strong force is repulsive at very short distances.
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.
 
  • #7
arivero
Gold Member
3,304
59
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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