PM = EM: Partially Massless Duality Invariance

TL;DR

The paper demonstrates that maximal-depth partially massless fields in de Sitter space admit a Maxwell-like electric-magnetic duality. By performing a field redefinition that maps the TT PM variables to a duality-compatible $(E,A)$ pair, the authors show that duality rotations act separately within each helicity sector and preserve the PM action, mirroring the dS Maxwell case. This result relies on conformal invariance in four dimensions and generalizes the duality concept to higher-spin, curved-background theories using a higher-rank curl operator. The work broadens the scope of duality symmetries in cosmological settings and suggests possible implications for PM field radiative interactions, though explicit couplings to charges require further study.

Abstract

In d=4 de Sitter space, novel conformally invariant photon-like theories consistently couple to charged matter. We show that these higher spin, maximal depth, partially massless systems enjoy a Maxwellian, "electric-magnetic" duality.