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arXiv · 0903.5176

Cosmological perturbations in SFT inspired non-local scalar field models

Alexey S. Koshelev·Sergey Yu. Vernov
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Abstract

We study cosmological perturbations in models with a single non-local scalar field originating from the string field theory description of the rolling tachyon dynamics. We construct the equation for the energy density perturbations of the non-local scalar field and explicitly prove that for the free field it is identical to a system of local cosmological perturbation equations in a particular model with multiple (maybe infinitely many) local free scalar fields.

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Alexey S. Koshelev, Sergey Yu. Vernov. 2012-07-16. Cosmological perturbations in SFT inspired non-local scalar field models. https://doi.org/10.1140/epjc%2Fs10052-012-2198-4

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