On Statistical Mechanics of Nonequilibrium Fluctuations

Stationary nonequilibrium statistical mechanics

Systems in stationary nonequilibrium are mechanical systems subject to nonconservative external forces and to thermostat forces which forbid indefinite increase of the energy and allow reaching statistically stationary states. A system Σ is described by the positions and velocities of its n particles X, Ẋ, with the particles positions confined to a finite volume container C0. If X = (x1, . . .,...

Elements of Nonequilibrium Statistical Mechanics

Currents in nonequilibrium statistical mechanics.

Nonzero currents characterize the nonequilibrium state in stochastic dynamics (or master equation) models of natural systems. In such models there is a matrix R of transition probabilities connecting the states of the system. We show that if the strength of a transition increases, so does the current along the corresponding bond. We also address the inverse problem: given a set of observed curr...

Nonequilibrium Statistical Mechanics of Open Classical Systems

We describe the ergodic and thermodynamical properties of chains of anharmonic oscillators coupled, at the boundaries, to heat reservoirs at positive and different temperatures. We discuss existence and uniqueness of stationary states, rate of convergence to stationarity, heat flows and entropy production, Kubo formula and Gallavotti-Cohen fluctuation theorem.

Nonequilibrium statistical mechanics of dividing cell populations.

We present and study a model for the nonequilibrium statistical mechanics of protein distributions in a proliferating cell population. Our model describes how the total protein variation is shaped by two processes: variation in protein production internal to the cells and variation in division and inheritance at the population level. It enables us to assess the contribution of each of these com...