Reheating in Models with Non-minimal Coupling in metric and Palatini formalisms

Abstract

We study reheating of inflationary models with general non-minimal coupling $K(\varphi )R$ with $K(\varphi )\sim \sqrt{V(\varphi )}$ where $R$ is the Ricci scalar and $V$ is the inflaton potential. In particular, when we take the monomial potential $K(\varphi )\propto {\varphi }^m$ with $m\in {\mathbb{Z}}_{+}$, we provide general analytic expressions for cosmological observables. We consider a wide range of non-minimal coupling $\xi \in [0,\infty )$ in metric and Palatini formalisms and derive the predictions for cosmological observables and the reheating temperature taking a general equation of state parameter $w_{\text{reh}}$.

Comments: 20 pages, 6 figures, v2: references added