Vainshtein Screening in Bimetric Cosmology

Understand

We demonstrate that the instabilities in linear cosmological perturbations in bimetric theory are the manifestation of the non-linear Vainshtein mechanism on an FRW background.

• The spin-2 mass serves as the cosmological Vainshtein scale in this case.
• This allows us to quantitatively address early universe cosmology.
• In particular, in a global analysis, we study data from the cosmic microwave background radiation and local measurements of the Hubble flow.