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arXiv · 2504.02809

Fractional attractors in light of the latest ACT observations

Christian Dioguardi·Antonio J. Iovino·Antonio Racioppi
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Abstract

In light of the latest results from ACT observations we review a class of potentials labeled as fractional attractors, that can originate from Palatini gravity. We show that, for certain choices of the scalar potential $V(\phi)$, the fractional attractors predict both a spectral index $n_s$ and a tensor-to-scalar ratio $r$ that fall within the $1\sigma$ region of the combined ACT+Planck data for a wide range of parameters. We also provide a numerical fit for the parameter space of this models in the case of a simple quadratic and quartic fractional potential.

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Christian Dioguardi, Antonio J. Iovino, Antonio Racioppi. 2025-04-03. Fractional attractors in light of the latest ACT observations. https://doi.org/10.1016/j.physletb.2025.139664

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