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arXiv · 1911.10918

Quantum Cosmology and the Inflationary Spectra from a Non-Minimally Coupled Inflaton

Abstract

We calculate the quantum gravitational corrections to the Mukhanov-Sasaki equation obtained by the canonical quantization of the inflaton-gravity system. Our approach, which is based on the Born-Oppenheimer decomposition of the resulting Wheeler-DeWitt equation, was previously applied to a minimally coupled inflaton. In this article we examine the case of a non minimally coupled inflaton and, in particular, the induced gravity case is also discussed. Finally, the equation governing the quantum evolution of the inflationary perturbations is derived on a de Sitter background. Moreover the problem of the introduction of time is addressed and a generalized method, with respect to that used for the minimal coupling case, is illustrated. Such a generalized method can be applied to the universe wave function when, through the Born-Oppenheimer factorization, we decompose it into a part which contains the minisuperspace degrees of freedom and another which describes the perturbations.

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BibTeXRIS

A. Y. Kamenshchik, A. Tronconi, G. Venturi. 2019-11-25. Quantum Cosmology and the Inflationary Spectra from a Non-Minimally Coupled Inflaton. https://doi.org/10.1103/physrevd.101.023534

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