2026/01/31 by Stefano Bellucci, Stefania De Matteo
Physics and Astronomy · #hep-th
21 pages. Substantially revised version with a new title. This version supersedes v1 and corrects the reduced Berezin-projection argument. The manuscript now distinguishes the unrestricted vector-spinor algebra from the exterior-polynomial first-order sector, proves the restricted classification theorem, and includes a worked integral-form superspace projection
arxiv created 2026/08/01 · arxiv updated 2026/08/04
We identify a minimal superspace projector that uniquely selects the Rarita Schwinger mass bilinear in four-dimensional N=1 supergravity. Working in a reduced superspace with a single fermionic direction, we show that Berezin projection of a canonical even supergeometric form isolates the unique Lorentz-invariant fermionic bilinear compatible with local supersymmetry. The construction is predynamical: it fixes the algebraic structure of the gravitino mass term independently of supersymmetry breaking mechanisms, background geometry, or matter couplings. We show that this projector embeds consistently into curved superspace, extends to N>1 theories, and clarifies the universality of the gravitino mass structure in supergravity.