Strong lensing constraints on bimetric massive gravity
  We derive dynamical and gravitational lensing properties of local sources in
the Hassan-Rosen bimetric gravity theory. Observations of elliptical galaxies
rule out values of the effective length-scale of the theory, in units of the
Hubble radius, in the interval 10^-6 < lambda_g/r_H < 10^-3, unless the
proportionality constant between the metrics at the background level is far
from unity, in which case general relativity is effectively restored for local
sources. In order to have background solutions resembling the concordance
cosmological model, without fine-tuning of the parameters of the model, we are
restricted to the upper interval, or lambda_g/r_H ~ 1. Except for a limited
range of parameter values, the Hassan-Rosen theory is thus consistent with the
observed lensing and dynamical properties of elliptical galaxies.
