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arXiv · hep-ph/9412232

A Note on the Finiteness of Curvature at Cosmic String Cusps

Ruth Gregory
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Abstract

We examine a Nambu-Goto string trajectory in the neighbourhood of a cusp and determine the extrinsic curvature invariants. These are demonstrated to be finite, in contradiction with naive expectation. Thus the Nambu action is a valid approximation for the motion of a cosmic string vortex even at cusps. This suggests that cusp annihilation is not a feasible mechanism for particle radiation from cosmic strings.

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Ruth Gregory. 1994-12-05. A Note on the Finiteness of Curvature at Cosmic String Cusps. https://arxiv.org/abs/hep-ph/9412232

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