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arXiv · 2512.16815

Quasi-pole inflation in metric-affine gravity

Antonio Racioppi
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Abstract

We propose a new mechanism for inflationary model building in the framework of metric-affine gravity. Such a mechanism involves an inflaton non-minimally coupled with the Holst invariant. If the non-minimal coupling function has a zero point and it is very steep at that same point, the corresponding inflaton kinetic function will feature a quasi-pole behaviour, implying a canonically normalized potential featuring an exponential plateau, regardless of the shape of the original inflaton potential. The inflationary predictions in such a region are equivalent to the ones of Starobinsky inflation.

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Antonio Racioppi. 2025-12-18. Quasi-pole inflation in metric-affine gravity. https://doi.org/10.1007/s10714-026-03548-9

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