Three faces of the second law. I. Master equation formulation

We propose a formulation of stochastic thermodynamics for systems subjected to nonequilibrium constraints
i.e. broken detailed balance at steady state and furthermore driven by external time-dependent forces. A
splitting of the second law occurs in this description leading to three second-law-like relations. The general
results are illustrated on specific solvable models. The present paper uses a master equation based approach.