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arXiv · 1011.4618

Evolution of cosmological perturbations in an RG-driven inflationary scenario

Adriano Contillo
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Abstract

A gauge-invariant, linear cosmological perturbation theory of an almost homogeneous and isotropic universe with dynamically evolving Newton constant G and cosmological constant $\Lambda$ is presented. The equations governing the evolution of the comoving fractional spatial gradients of the matter density, G and $\Lambda$ are thus obtained. Explicit solutions are discussed in cosmologies, featuring an accelerated expansion, where both G and $\Lambda$ vary according to renormalization group equations in the vicinity of an ultraviolet fixed point. Finally, a similar analysis is carried out in the late universe regime described by the part of the renormalization group trajectory close to the gaussian fixed point.

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Adriano Contillo. 2010-11-20. Evolution of cosmological perturbations in an RG-driven inflationary scenario. https://doi.org/10.1103/physrevd.83.085016

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