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arXiv · 2508.11596

Breaking the Strings: the signatures of Cosmic String Loop Fragmentation

Pierre Auclair
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Abstract

We study the impact of fragmentation on the cosmic string loop number density, using an approach inspired by the three-scale model and a Boltzmann equation. We build a new formulation designed to be more amenable to numerical resolution and present two complementary numerical methods to obtain the full loop distribution including the effect of fragmentation and gravitational radiation. We show that fragmentation generically predicts a decay of the loop number density on large scales and a deviation from a pure power-law. We expect fragmentation to be crucial for the calibration of loop distribution models.

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Pierre Auclair. 2025-08-15. Breaking the Strings: the signatures of Cosmic String Loop Fragmentation. https://doi.org/10.1088/1475-7516%2F2025%2F12%2F020

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