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Weak-Field Gravity of Circular Cosmic Strings

Shane J. Hughes·Des J. Mc Manus·Michel A. Vandyck
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Abstract

A weak-field solution of Einstein's equations is constructed. It is generated by a circular cosmic string externally supported against collapse. The solution exhibits a conical singularity, and the corresponding deficit angle is the same as for a straight string of the same linear energy density. This confirms the deficit-angle assumption made in the Frolov-Israel-Unruh derivation of the metric describing a string loop at a moment of time symmetry.

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Shane J. Hughes, Des J. Mc Manus, Michel A. Vandyck. 1992-11-09. Weak-Field Gravity of Circular Cosmic Strings. https://doi.org/10.1103/physrevd.47.468

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