Analytical constraints on bimetric gravity
  Ghost-free bimetric gravity is an extension of general relativity, featuring
a massive spin-2 field coupled to gravity. We parameterize the theory with a
set of observables having specific physical interpretations. For the background
cosmology and the static, spherically symmetric solutions (for example
approximating the gravitational potential of the solar system), there are four
directions in the parameter space in which general relativity is approached.
Requiring that there is a working screening mechanism and a nonsingular
evolution of the Universe, we place analytical constraints on the parameter
space which rule out many of the models studied in the literature. Cosmological
solutions where the accelerated expansion of the Universe is explained by the
dynamical interaction of the massive spin-2 field rather than by a cosmological
constant, are still viable.
