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arXiv · 2405.14653

Inflation in a scalar-vector gravity theory

Manuel Gonzalez-Espinoza·Ramon Herrera
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Abstract

We study the possibility that inflation is driven by a scalar field together with a vector field minimally coupled to gravity. By assuming an effective potential that incorporates both fields into the action, we explore two distinct scenarios: one where the fields interact and another where they do not. In this context, we find different analytical solutions to the background scalar-vector fields dynamics during the inflationary scenario considering the slow-roll approximation. Besides, general conditions required for these models of two fields to be realizable are determined and discussed. From the cosmological perturbations, we consider a local field rotation, and then we determine these perturbations (scalar and tensor) during inflation, and we also utilize recent cosmological observations for constraining the parameter-space in these scalar-vector inflationary models.

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Manuel Gonzalez-Espinoza, Ramon Herrera. 2024-05-23. Inflation in a scalar-vector gravity theory. https://doi.org/10.1016/j.aop.2024.169876

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