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Scaling of cosmic string loops

Vitaly Vanchurin·Ken D. Olum·Alexander Vilenkin
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Abstract

We study the spectrum of loops as a part of a complete network of cosmic strings in flat spacetime. After a long transient regime, characterized by production of small loops at the scale of the initial conditions, it appears that a true scaling regime takes over. In this final regime the characteristic length of loops scales as $0.1 t$, in contrast to earlier simulations which found tiny loops. We expect the expanding-universe behavior to be qualitatively similar. The large loop sizes have important cosmological implications. In particular, the nucleosynthesis bound becomes $Gμ\lesssim 10^{-7}$, much tighter than before.

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Vitaly Vanchurin, Ken D. Olum, Alexander Vilenkin. 2006-06-20. Scaling of cosmic string loops. https://doi.org/10.1103/physrevd.74.063527

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