Fractional attractors in light of the latest ACT observations

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 ) , the fractional attractors predict both a spectral index n s and a tensor-to-scalar ratio r that fall within the 1 σ 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.

• EC
  European Cooperation in Science and Technology

  Awards: TK202, RVTT3, PRG1055, CA21136
• ET
  Eesti Teadusagentuur