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arXiv · 2411.16590

More accurate gravitational wave backgrounds from cosmic strings

Jeremy M. Wachter·Ken D. Olum·Jose J. Blanco-Pillado
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Abstract

We derive a general procedure for calculating the gravitational wave background (GWB) from cosmic string loops whose typical shape evolves over time, as in gravitational backreaction. Using the results of a large-scale study of numerical gravitational backreaction on Nambu-Goto cosmic string loops, we construct GWBs of backreacted cosmic strings for a range of tensions and frequencies of cosmological interest, and compare them to current and upcoming gravitational wave detectors. The GWBs are lower than prior predictions by anywhere from a few percent to around 30\%, depending on the frequency and tension in question.

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Jeremy M. Wachter, Ken D. Olum, Jose J. Blanco-Pillado. 2024-11-25. More accurate gravitational wave backgrounds from cosmic strings. https://arxiv.org/abs/2411.16590

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