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arXiv · 1005.1680

Non-linear dynamics of cosmic strings with non-scaling loops

Vitaly Vanchurin
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Abstract

At early stages the dynamics of cosmic string networks is expected to be influenced by an excessive production of small loops at the scales of initial conditions l_{min}. To understand the late time behavior we propose a very simple analytical model of strings with a non-scaling population of loops. The complicated non-linear dynamics is described by only a single parameter N ~ 2/(1-C(l_{min})) where C(l) is a correlation function of the string tangent vectors. The model predicts an appearance of two new length scales: the coherence length ξ~ t/N^2 and the cross-correlation length χ~ t/N. At the onset of evolution N ~ 10 and at late times N is expected to grow logarithmically due to cosmological stretching and emission of small loops. The very late time evolution might be modified further when the gravitational back-reaction scale grows larger than l_{min}.

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Vitaly Vanchurin. 2010-08-02. Non-linear dynamics of cosmic strings with non-scaling loops. https://doi.org/10.1103/physrevd.82.063503

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