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General Relativity as an Attractor in Scalar-Tensor Stochastic Inflation

Juan Garcia-Bellido·David Wands
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Abstract

Quantum fluctuations of scalar fields during inflation could determine the very large-scale structure of the universe. In the case of general scalar-tensor gravity theories these fluctuations lead to the diffusion of fundamental constants like the Planck mass and the effective Brans--Dicke parameter, $ω$. In the particular case of Brans--Dicke gravity, where $ω$ is constant, this leads to runaway solutions with infinitely large values of the Planck mass. However, in a theory with variable $ω$ we find stationary probability distributions with a finite value of the Planck mass peaked at exponentially large values of $ω$ after inflation. We conclude that general relativity is an attractor during the quantum diffusion of the fields.

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BibTeXRIS

Juan Garcia-Bellido, David Wands. 1995-03-27. General Relativity as an Attractor in Scalar-Tensor Stochastic Inflation. https://doi.org/10.1103/physrevd.52.5636

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