Résumé:

'll discuss a recently proposed tetrad formulation of bimetric gravity. Like generic massive gravity theories, bigravity models suffer from the presence of a certain ghost scalar field. Recently, it was argued however that there are 3 potentials which are free from this pathology. Although the original formulation of these potentials is quite nasty, they take a beautiful form in terms of the tetrads. I'll present the canonical analysis of this tetrad reformulation and confirm that it is ghost-free describing the seven degrees of freedom of a massless and a massive gravitons.