Dynamical Dark Energy in Minimally Modified Gravity
  Minimally modified gravity is a class of models with only the two tensor
degrees of freedom as in general relativity. Using the framework with auxiliary
constraints these models can maintain a dynamical cosmological background. The
form of the constraints is thereby restricted by the requirement of dynamical
dark energy and the avoidance of a breakdown of perturbation theory. Studying
the linear perturbations around the FLRW background the results are, however,
quite insensitive to the details of the constraints leading to a modified
effective gravitational constant or a non-vanishing sound speed for dust.
