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Fractional attractors in light of the latest ACT observations

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arxiv 2504.02809 v2 pith:X4BQMSGI submitted 2025-04-03 gr-qc astro-ph.COhep-ph

classification gr-qcastro-ph.COhep-ph
keywords fractionalattractorslatestlightobservationspotentialcasecertain
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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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Forward citations

Cited by 21 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

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