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arXiv · 1508.02317

Disruption of Cosmic String Wakes by Gaussian Fluctuations

Robert H. Brandenberger·Oscar F. Hernández·Disrael C. N. da Cunha
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Abstract

We study the stability of cosmic string wakes against the disruption by the dominant Gaussian fluctuations which are present in cosmological models. We find that for a string tension given by $G \mu = 10^{-7}$ wakes remain locally stable until a redshift of $z = 6$, and for a value of $G \mu = 10^{-14}$ they are stable beyond a redshift of $z = 20$. We study a global stability criterion which shows that wakes created by strings at times after $t_{eq}$ are identifiable up to the present time, independent of the value of $G \mu$. Taking into account our criteria it is possible to develop strategies to search for the distinctive position space signals in cosmological maps which are induced by wakes.

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Robert H. Brandenberger, Oscar F. Hernández, Disrael C. N. da Cunha. 2015-08-10. Disruption of Cosmic String Wakes by Gaussian Fluctuations. https://doi.org/10.1103/physrevd.93.123501

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