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arXiv · 2001.03770

Massless Cosmic Strings in Spacetimes with Global Parabolic Isometries

Dmitri V. Fursaev
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Abstract

A class of curved spacetimes with global parabolic isometries (GPI) is introduced. These isometries have fixed point sets on two-dimensional null surfaces which can be interpreted as worldsheets of massless cosmic strings. Back reaction effects of the strings in such spacetimes can be described exactly, in terms of a nontrivial holonomy at the worldsheet. We show that the GPI spacetimes are type $N$ geometries of the Petrov classification. We describe a number of features of these spacetimes, including properties of Killing horizons associated to GPI. As an example, we consider a circular massless cosmic string in the de Sitter universe and present the metric in new coordinates centered at the string worldsheet.

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Dmitri V. Fursaev. 2020-01-11. Massless Cosmic Strings in Spacetimes with Global Parabolic Isometries. https://doi.org/10.1134/s1063779620040279

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