TY  - JOUR
AU  - del Rio, A.
AU  - Agullo, I.
PY  - 2023
DA  - 2023//
TI  - Chiral fermion anomaly as a memory effect
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 105025
EP  - 22pp
VL  - 108
IS  - 10
PB  - Amer Physical Soc
AB  - We study the nonconservation of the chiral charge of Dirac fields between past and future null infinity due to the Adler-Bell-Jackiw chiral anomaly. In previous investigations [A. del Rio, Phys. Rev. D 104, 065012 (2021)], we found that this charge fails to be conserved if electromagnetic sources in the bulk emit circularly polarized radiation. In this article, we unravel yet another contribution coming from the nonzero, infrared "soft" charges of the external, electromagnetic field. This new contribution can be interpreted as another manifestation of the ordinary memory effect produced by transitions between different infrared sectors of Maxwell theory, but now on test quantum fields rather than on test classical particles. In other words, a flux of electromagnetic waves can leave a memory on quantum fermion states in the form of a permanent, net helicity. We elaborate this idea in both 1 + 1 and 3 + 1 dimensions. We also show that, in sharp contrast, gravitational infrared charges do not contribute to the fermion chiral anomaly.
SN  - 2470-0010
UR  - https://arxiv.org/abs/2308.06330
UR  - https://doi.org/10.1103/PhysRevD.108.105025
DO  - 10.1103/PhysRevD.108.105025
LA  - English
N1  - WOS:001121689000004
ID  - delRio+Agullo2023
ER  -