  Generalized Langevin equation for characteristic functional of many-electron
system dynamically interacting with a thermostat and besides subjected to
external perturbation and observation is derived and formulated in terms of
one-particle but stochastic density matrix. The scheme naturally includes also
direct electron-electron interactions. Corresponding approximate Fokker-Plank
kinetic equation is discussed. We point out that it possesses continuous
degeneracy of stationary solution and therefore can hide long-correlated
fluctuations of electron transport even if thermostat noise is
short-correlated.
