Stability of sigma-model strings and textures

@article{Ward2002StabilityOS,
  title={Stability of sigma-model strings and textures},
  author={Richard S. Ward},
  journal={Classical and Quantum Gravity},
  year={2002},
  volume={19}
}
  • R. S. Ward
  • Published 14 January 2002
  • Mathematics, Physics
  • Classical and Quantum Gravity
In flat spacetime, sigma-model strings and textures are both unstable: they tend to collapse (and subsequently decay). With sufficient cosmological expansion, however, they are stable in a generalized sense: a small perturbation will cause them to change their shape, but they do not decay. The current rate of expansion is sufficient to stabilize strings, but not textures. 
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