Massive higher spin fields in (A)dS and in interaction

Abstract

I outline a series of results obtained in collaboration with A. Waldron on the properties of massive higher (s > 1) spin fields in cosmological, constant curvature, backgrounds and the resulting unexpected quantitative effects on their degrees of freedom and unitarity properties. The dimensional parameter Λ extends the flat space m-line to a (Λ, m) “phase” plane in which these novel phenomena unfold. In this light, I discuss a possible partial resurrection of deSitter supergravity. I will also list the well-known problems of coupling these systems to gravity and, for complex fields, to electromagnetism, systematizing some of the occasionally misunderstood obstacles to interactions, particularly for s = 3/2 and 2.