Infrared-modified gravities and massive gravitons
V.A. Rubakov a
P.G. Tinyakov a, b
a Institute for Nuclear Research, Russian Academy of Sciences, prosp. 60-letiya Oktyabrya 7a, Moscow, 117312, Russian Federation
b Service de Physique Théorique, Université Libre de Bruxelles, CP225, bld. du Triomphe, Bruxelles, B-1050, Belgium
We review some theoretical and phenomenological aspects of massive gravities in 4 dimensions. We start from the Fierz-Pauli theory with Lorentz-invariant mass terms and then proceed to Lorentz-violating masses. Unlike the former theory, some models with Lorentz violation have no pathologies in the spectrum in flat and nearly flat backgrounds and lead to an interesting phenomenology.