The introduction of Dark Matter-neutrino interactions modifies the Cosmic Microwave Background (CMB) angular power spectrum at all scales, thus affecting the reconstruction of the cosmological parameters. Such interactions can lead to a slight increase of the value of H0 and a slight decrease of σ8, which can help reduce somewhat the tension between the CMB and lensing or Cepheids datasets. Here we show that it is impossible to solve both tensions simultaneously. While the 2015 Planck temperature and low multipole polarisation data combined with the Cepheids datasets prefer large values of the Hubble rate (up to H0=72.1−1.7+1.5km/s/Mpc, when Neff is free to vary), the σ8 parameter remains too large to reduce the σ8 tension. Adding high multipole Planck polarization data does not help since this data shows a strong preference for low values of H0, thus worsening current tensions, even though they also prefer smaller value of σ8.
@article{arxiv.1710.02559,
title = {Reducing the $H_0$ and $\sigma_8$ tensions with Dark Matter-neutrino interactions},
author = {Eleonora Di Valentino and Céline Bøehm and Eric Hivon and François R. Bouchet},
journal= {arXiv preprint arXiv:1710.02559},
year = {2018}
}