Speaker
Adrian del Rio
Description
Axial-type anomalies predicted by quantum field theory in curved spacetime are determined by the Chern-Pontryagin invariant of the spacetime background. I will show that this geometric quantity is non-zero in spacetimes admitting gravitational radiation that propagates to future null infinity with an excess of one polarization mode over the other. I will further argue that typical scenarios where this gravitational asymmetry occurs include mergers of precessing binary black holes or in head-on collisions of black holes with misaligned spins, since these systems are not even under parity transformations. Some applications in the context of the electric-magnetic duality anomaly will be discussed.
