We point out that the duality symmetry of free electromagnetism does not hold in the quantum theory if an arbitrary classical gravitational background is present. The symmetry breaks in the process of renormalization, as also happens with conformal invariance. We show that a similar duality anomaly appears for a massless scalar field in 1+1 dimensions.
Publication Source (Journal or Book title)
Physical Review D - Particles, Fields, Gravitation and Cosmology
Agullo, I., Landete, A., & Navarro-Salas, J. (2014). Electric-magnetic duality and renormalization in curved spacetimes. Physical Review D - Particles, Fields, Gravitation and Cosmology, 90 (12) https://doi.org/10.1103/PhysRevD.90.124067