Cosmology based on $f(R)$ gravity with ${\cal O}(1)$ eV sterile neutrino

Understand

We address the cosmological role of an additional ${\cal O}(1)$ eV sterile neutrino in modified gravity models.

• We confront the present cosmological data with predictions of the FLRW cosmological model based on a variant of $f(R)$ modified gravity proposed by one of the authors previously.
• This viable cosmological model which deviation from general relativity with a cosmological constant $\Lambda$ decreases as $R^{-2n}$ for large, but not too large values of the Ricci scalar $R$ provides an alternative explanation of present dark energy and the accelerated expansion of the Universe.
• Various up-to-date cosmological data sets exploited include Planck CMB anisotropy, CMB lensing potential, BAO, cluster mass function and Hubble constant measurements.