Analytic solutions in non-linear massive gravity
  We study spherically symmetric solutions in a covariant massive gravity
model, which is a candidate for a ghost-free non-linear completion of the
Fierz-Pauli theory. There is a branch of solutions that exhibits the Vainshtein
mechanism, recovering General Relativity below a Vainshtein radius given by
$(r_g m^2)^{1/3}$, where $m$ is the graviton mass and $r_g$ is the
Schwarzschild radius of a matter source. Another branch of exact solutions
exists, corresponding to Schwarzschild-de Sitter spacetimes where the curvature
scale of de Sitter space is proportional to the mass squared of the graviton.
