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arXiv · 1306.5332

Super-accelerating bouncing cosmology in asymptotically-free non-local gravity

Gianluca Calcagni·Leonardo Modesto·Piero Nicolini
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Abstract

Recently, evidence has been collected that a class of gravitational theories with certain non-local operators is renormalizable. We consider one such model which, at the linear perturbative level, reproduces the effective non-local action for the light modes of bosonic closed string-field theory. Using the property of asymptotic freedom in the ultraviolet and fixing the classical behavior of the scale factor at late times, an algorithm is proposed to find general homogeneous cosmological solutions valid both at early and late times. Imposing a power-law classical limit, these solutions (including anisotropic ones) display a bounce, instead of a big-bang singularity, and super-accelerate near the bounce even in the absence of an inflaton or phantom field.

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Gianluca Calcagni, Leonardo Modesto, Piero Nicolini. 2014-08-24. Super-accelerating bouncing cosmology in asymptotically-free non-local gravity. https://doi.org/10.1140/epjc%2Fs10052-014-2999-8

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