  The anomalous generation of chirality with mass effects via the axial Ward
identity and its dependence on the Schwinger mechanism is reviewed, utilizing
parity violating homogeneous electromagnetic background fields. The role vacuum
asymptotic states play on the interpretation of expectation values is examined.
It is discussed that observables calculated with an in-out scattering matrix
element predict a scenario under Euclidean equilibrium. A notable ramification
of which is a vanishing of the chiral anomaly. In contrast, it is discussed
observables calculated under an in-in, or real-time, formalism predict a
scenario out-of equilibrium, and capture effects of mean produced particle
anti-particle pairs due to the Schwinger mechanism. The out-of equilibrium
chiral anomaly is supplemented with exponential quadratic mass suppression as
anticipated for the Schwinger mechanism. Similar behavior in and out-of
equilibrium is reviewed for applications including the chiral magnetic effect
and chiral condensate.
