High Energy Theory Seminar

We construct all supergravity theories that can be obtained through factorized projections of N = 8 supergravity, exposing their double-copy structure, and calculate their one-loop four-point scattering amplitudes. We derive representations of gluon amplitudes in N=1 and N=2 theories obeying color/kinematics duality and discuss their properties vis a vis those of N=4 super-Yang-Mills amplitudes and highlight the contribution to supergravity amplitudes of terms that integrate to zero. We also discuss a large (but not exhaustive) set of projections leading to theories with no obvious double-copy structure and observe a unified structure in both matter and gravity amplitudes. For N=4 supergravity with and without further matter vector multiplets we discuss the anomaly of a U(1) subgroup of the duality group, construct the anomalous part of the one-loop effective action and identify the reflection of the anomaly in the supergravity S-matrix. A similar anomalous symmetry exists for N<4 supergravities as well.