PT Journal
AU Agullo, I
   del Rio, A
   Navarro-Salas, J
TI Electromagnetic Duality Anomaly in Curved Spacetimes
SO Physical Review Letters
JI Phys. Rev. Lett.
PY 2017
BP 111301
EP 5pp
VL 118
IS 11
DI 10.1103/PhysRevLett.118.111301
LA English
AB The source-free Maxwell action is invariant under electric-magnetic duality rotations in arbitrary spacetimes. This leads to a conserved classical Noether charge. We show that this conservation law is broken at the quantum level in the presence of a background classical gravitational field with a nontrivial Chern-Pontryagin invariant, in parallel with the chiral anomaly for massless Dirac fermions. Among the physical consequences, the net polarization of the quantum electromagnetic field is not conserved.
ER