  We construct a unifying theory of geometric effects in mesoscopic stochastic
kinetics. We demonstrate that the adiabatic pump and the reversible ratchet
effects, as well as similar new phenomena in other domains, such as in
epidemiology, all follow from geometric phase contributions to the effective
action in the stochastic path integral representation of the moment generating
function. The theory provides the universal technique for identification,
prediction and calculation of pump-like phenomena in an arbitrary mesoscopic
stochastic framework.
