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arXiv · 2403.08530

Inflation and reheating in quadratic metric-affine gravity with derivative couplings

Ioannis D. Gialamas·Theodoros Katsoulas·Kyriakos Tamvakis
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Abstract

Within the framework of metric-affine theories of gravity, where both the metric and connection are treated as independent variables, we consider actions quadratic in the Ricci scalar curvature coupled non-minimally to a scalar field through derivative couplings. Our analysis delves into the inflationary predictions, revealing their consistency with the latest observational constraints across a wide range of parameters. This compatibility permits adjustments such as an increase in the spectral index and a reduction in the tensor-to-scalar ratio. While we do not propose a specific reheating mechanism, our analysis demonstrates that within the quadratic model of inflation, the maximum reheating temperature can reach $\sim 3\times10^{15}\, {\rm GeV}$.

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Ioannis D. Gialamas, Theodoros Katsoulas, Kyriakos Tamvakis. 2024-03-13. Inflation and reheating in quadratic metric-affine gravity with derivative couplings. https://doi.org/10.1088/1475-7516%2F2024%2F06%2F005

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