Natural inflation in Palatini $F(R,X)$
General Relativity and Quantum Cosmology
2025-12-22 v3
Abstract
In the context of Palatini gravity, models, with X the inflaton kinetic term, are characterized by the appealing property of generating asymptotically flat inflaton potentials, exactly like the more commonly studied Palatini models, but without the complication of non-canonical inflaton kinetic terms in the Einstein frame. In this paper, we study the case of a Jordan frame potential which is positive and bounded, specifically, natural inflation. We compute the CMB observables and show that for a wide class of theories, including the quadratic one, natural inflation is still viable.
Cite
@article{arxiv.2503.16324,
title = {Natural inflation in Palatini $F(R,X)$},
author = {N. Bostan and R. H. Dejrah and C. Dioguardi and A. Racioppi},
journal= {arXiv preprint arXiv:2503.16324},
year = {2025}
}
Comments
15 pages, 5 figures, references added, a brief analysis for subPlanckian M added, matches the published version