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Cosmological Perturbations in Renormalization Group Derived Cosmologies

A. Bonanno·M. Reuter
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Abstract

A linear cosmological perturbation theory of an almost homogeneous and isotropic perfect fluid Universe with dynamically evolving Newton constant $G$ and cosmological constant $Λ$ is presented. A gauge-invariant formalism is developed by means of the covariant approach, and the acoustic propagation equations governing the evolution of the comoving fractional spatial gradients of the matter density, $G$, and $Λ$ are thus obtained. Explicit solutions are discussed in cosmologies where both $G$ and $Λ$ vary according to renormalization group equations in the vicinity of a fixed point.

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BibTeXRIS

A. Bonanno, M. Reuter. 2003-09-12. Cosmological Perturbations in Renormalization Group Derived Cosmologies. https://doi.org/10.1142/s0218271804003809

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