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arXiv · 1812.04584

Dynamics of junctions and the multi-tension velocity-dependent one-scale model

I. Yu. Rybak·A. Avgoustidis·C. J. A. P. Martins
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Abstract

The dynamics of string junctions and their influence on the evolution of cosmic superstring networks are studied in full detail. We review kinematic constraints for colliding strings in a Friedmann-Lema\^itre-Robertson-Walker background and obtain the average distribution of possible string configurations after string collisions. The study of small-scale structure enables us to investigate the average growth/reduction rate of string junctions for a given cosmic string network. Incorporating the averaged junction dynamics into the velocity-dependent one-scale model for multi-tension string networks, we improve the semi-analytic description and quantitative understanding of cosmic superstring network evolution.

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I. Yu. Rybak, A. Avgoustidis, C. J. A. P. Martins. 2018-12-11. Dynamics of junctions and the multi-tension velocity-dependent one-scale model. https://doi.org/10.1103/physrevd.99.063516

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