We consider the effects of non-minimal couplings to curvature of the form $\xi_S S^2 R$, for three types of scalars: the Higgs boson, the inflaton, and a scalar dark matter candidate. We compute the abundance of dark matter produced by these non-minimal couplings to gravity and compare to similar results with minimal couplings. We also compute the contribution to the radiation bath during reheating. The main effect is a potential augmentation of the maximum temperature during reheating. A model independent limit of $\mathcal{ O}(10^{ 12})$ GeV is obtained. For couplings $\xi_S \gtrsim \mathcal{ O}(1)$, these dominate over minimal gravitational interactions.
Categories: hep-ph astro-ph.CO hep-th