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arXiv · 2404.09107

Power law coupling Higgs-Palatini inflation with a congruence between physical and geometrical symmetries

Abstract

In this paper we investigate a power law coupling Higgs inflationary model in which the background geometry is determined by the Palatini's variational principle. The geometrical symmetries of the background geometry determine the invariant form of the action of the model and the background geometry resulted is of the Weyl-integrable type. The invariant action results also invariant under the $U(1)$ group, which in general is not compatible with the Weyl group of invariance of the background geometry. However, we found compatibility conditions between the geometrical and physical symmetries of the action in the strong coupling limit. We found that if we start with a non-minimally coupled to gravity action, when we impose the congruence between the both groups of symmetries we end with an invariant action of the scalar-tensor type. We obtain a nearly scale invariant power spectrum for the inflaton fluctuations for certain values of some parameters of the model. Also we obtain va\-lues for the tensor to scalar ratio in agreement with PLANCK and BICEP observational data: $r<0.032$.

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José Edgar Madriz Aguilar, Diego Allan Reyna, Mariana Montes. 2025-06-27. Power law coupling Higgs-Palatini inflation with a congruence between physical and geometrical symmetries. https://arxiv.org/abs/2404.09107

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