Geometric multipliers and partial teleparallelism in Poincar\'e gauge theory

Abstract

The dynamics of the torsion-powered teleparallel theory are only viable because thirty-six multiplier fields disable all components of the Riemann--Cartan curvature. We generalise this suggestive approach by considering Poincar\'e gauge theory in which sixty such `geometric multipliers' can be invoked to disable any given irreducible part of the curvature, or indeed the torsion. Torsion theories motivated by a weak-field analysis frequently suffer from unwanted dynamics in the strong-field regime, such as the activation of ghosts. By considering the propagation of massive, parity-even vector torsion, we explore how geometric multipliers may be able to limit strong-field departures from the weak-field Hamiltonian constraint structure, and consider their tree-level phenomena.