On stars, galaxies and black holes in massive bigravity
  In this paper we study the phenomenology of stars and galaxies in massive
bigravity. We give parameter conditions for the existence of viable star
solutions when the radius of the star is much smaller than the Compton
wavelength of the graviton. If these parameter conditions are not met, we
constrain the ratio between the coupling constants of the two metrics, in order
to give viable conditions for e.g. neutron stars. For galaxies, we put
constraints on both the Compton wavelength of the graviton and the conformal
factor and coupling constants of the two metrics. The relationship between
black holes and stars, and whether the former can be formed from the latter, is
discussed. We argue that the different asymptotic structure of stars and black
holes makes it unlikely that black holes form from the gravitational collapse
of stars in massive bigravity.
