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arXiv · 2412.17738

Symmetry-breaking inflation in non-minimal metric-affine gravity

Ioannis D. Gialamas·Antonio Racioppi
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Abstract

We study symmetry-breaking inflation within the framework of metric-affine gravity. By introducing a non-minimal coupling, $\beta(\phi)\tilde{\cal R}$, between the Holst invariant and the inflaton, both small-field and large-field inflationary predictions can be brought into agreement with the latest observational constraints. Remarkably, even for sub-Planckian vacuum expectation values, appropriately chosen values of $\beta(\phi)$ enable viable inflation, a scenario previously considered unattainable.

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Ioannis D. Gialamas, Antonio Racioppi. 2024-12-23. Symmetry-breaking inflation in non-minimal metric-affine gravity. https://arxiv.org/abs/2412.17738

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