Supersymmetric Massive Gravity

We initiate a systematic study of the self-interactions of a massive spin-2 graviton consistent with up to N = 4 supersymmetry. Using a recently developed massive on-shell superspace formalism, we construct the most general set of cubic massive graviton amplitudes in a form with all supersymmetry and Lorentz invariance manifest. We find that for N >= 3 supersymmetry, the family of consistent interactions coincide with those of the ghost-free dRGT model. For N = 4 (maximal) supersymmetry there is a single consistent cubic interaction which coincides with the unique structure required for the absence of asymptotic superluminality. Additionally, we discuss the structure of interactions in the high-energy limit, connections to supersymmetric Galileons and the possibility of a supersymmetric massive double copy.

Automated summary

This study initiates a systematic exploration of the self-interactions of a massive spin-2 graviton consistent with up to N = 4 supersymmetry. By employing a recently developed massive on-shell superspace formalism, the most general set of cubic massive graviton amplitudes is constructed in a form that manifests both supersymmetry and Lorentz invariance. It is found that, for N ≥ 3 supersymmetry, the family of consistent interactions coincides with those of the ghost-free dRGT model. In the case of N = 4 supersymmetry, there exists a single consistent cubic interaction which coincides with the unique structure required for the absence of asymptotic superluminality. Furthermore, the structure of interactions in the high-energy limit, connections to supersymmetric Galileons, and the possibility of a supersymmetric massive double copy are discussed.