Torsional degrees of freedom in AdS4/CFT3

Abstract

We discuss the holographic implications of torsional degrees of freedom in the context of AdS4/CFT3, emphasizing in particular their physical interpretation as carriers of the non-trivial gravitational magnetic field, i.e. the part of the gravitational magnetic field not determined by the frame field. As a concrete example we present a new exact 4d gravitational background with torsion and argue that it corresponds to the holographic dual of a 3d system undergoing parity symmetry breaking. Finally, we compare our new gravitational background with known wormhole solutions - with and without cosmological constant - and argue that they can all be unified under an intriguing "Kalb-Ramond superconductivity" framework.