Solid Soft Theorems
  We derive cosmological soft theorems for solids coupled to gravity. To this
end, we first derive all cosmological adiabatic modes for solids, which display
the interesting novelty of non-vanishing anisotropic stresses on large scales.
Then, from the corresponding symmetries of the action of perturbations we
compute the leading order related soft theorems using the operator product
expansion. For the scalar bispectrum, we re-derive the result that Maldacena's
consistency relation is recovered only upon angular averaging over the long
mode direction. In addition, we find theorems for soft tensor and vector
perturbations. In passing, we also clarify the derivation of these soft
theorems in gauges where no residual diffeomorphisms exist.
