Explaining the origin of the acceleration of the expansion of the Universe remains as
challenging as ever. In this review, we present different approaches from dark energy to …

We write down the teleparallel equivalent to Hassan–Rosen bigravity, which is written using
a torsionful but curvature-free connection. The theories only differ by a boundary term. The …

We study the implications of the recent detection of gravitational waves emitted by a pair of
merging neutron stars and their electromagnetic counterpart, events GW170817 and …

We present a comprehensive analysis of classical scalar, vector and tensor cosmological
perturbations in ghost-free massive bigravity. In particular, we find the full evolution …

In this paper, we establish the correspondence between ghost-free bimetric theory and a
class of higher derivative gravity actions, including conformal gravity and new massive …

The ghost-free theory of massive gravity with two dynamical metrics has been shown to
produce viable cosmological expansion, where the late-time acceleration of the Universe is …

A bstract The ghost-free bimetric theory describes interactions of gravity with another spin-2
field in terms of two Lorentzian metrics. However, if the two metrics do not admit compatible …

We study the cosmic expansion history of massive bigravity with a viable matter coupling
which treats both metrics on equal footing. We derive the Friedmann equation for the …

We construct a wide class of black hole solutions to the general theory of ghost-free
multimetric gravity in arbitrary spacetime dimension, extending and generalizing the known …

We investigate the cosmological perturbations around FLRW solutions to non-linear
massive gravity with a new effective coupling to matter proposed recently. Unlike the case …