Conformally coupled inflation

Valerio Faraoni

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arXiv · 1309.4900

Conformally coupled inflation

Valerio Faraoni

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Abstract

A massive scalar field in a curved spacetime can propagate along the light cone, a causal pathology, which can, in principle, be eliminated only if the scalar couples conformally to the Ricci curvature of spacetime. This property mandates conformal coupling for the field driving inflation in the early universe. During slow-roll inflation, this coupling can cause super-acceleration and, as a signature, a blue spectrum of primordial gravitational waves.

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Valerio Faraoni. 2013-09-19. Conformally coupled inflation. https://arxiv.org/abs/1309.4900

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