English

Fractional attractors in light of the latest ACT observations

General Relativity and Quantum Cosmology 2025-06-23 v2 Cosmology and Nongalactic Astrophysics High Energy Physics - Phenomenology

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(ϕ)V(\phi), the fractional attractors predict both a spectral index nsn_s and a tensor-to-scalar ratio rr that fall within the 1σ1\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.

Keywords

Cite

@article{arxiv.2504.02809,
  title  = {Fractional attractors in light of the latest ACT observations},
  author = {Christian Dioguardi and Antonio J. Iovino and Antonio Racioppi},
  journal= {arXiv preprint arXiv:2504.02809},
  year   = {2025}
}

Comments

4 pages, 2 figures. v2: PLB version