PT Journal
AU Beltran-Palau, P
   Ferreiro, A
   Navarro-Salas, J
   Pla, S
TI Breaking of adiabatic invariance in the creation of particles by electromagnetic backgrounds
SO Physical Review D
JI Phys. Rev. D
PY 2019
BP 085014
EP 12pp
VL 100
IS 8
DI 10.1103/PhysRevD.100.085014
LA English
AB Particles are spontaneously created from the vacuum by time-varying gravitational or electromagnetic backgrounds. It has been proven that the particle number operator in an expanding universe is an adiabatic invariant. In this paper we show that, in some special cases, the expected adiabatic invariance of the particle number fails in presence of electromagnetic backgrounds. In order to do this, we consider as a prototype a Sauter-type electric pulse. Furthermore, we also show a close relation between the breaking of the adiabatic invariance and the emergence of the axial anomaly.
ER