One of the main objectives of statistical mechanics is understanding the statistical behavior of systems using their microscopic properties. In particular, great success was obtained in studying systems in equilibrium, where their macroscopic properties, like pressure or temperature, do not change in time. The natural step forward in this kind of investigation is the understanding of the statistical behavior of systems out-of-equilibrium, where the macroscopic properties change over time.
One possible way to produce a system in an out-of-equilibrium regime is by changing its external parameters. For example, one can modify the frequency of a harmonic oscillator, as it is done in optical tweezers. From the microscopic point of view, the dynamics of the system are modeled by non-autonomous differential equations, where the energy is modified along the process. Also, its statistical description faces similar technical difficulties. Approximations are then necessary to be employed to gain some information on some regimes. One of particular success is the linear-response theory, where the driving is weak with an arbitrary rate of change. My line of research focuses thus on using linear-response theory to obtain statistical information on systems in out-of-equilibrium regimes.
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Pierre Nazé and Marcus V. S. Bonança
Adiabatic processes like isothermal processes
Pierre Nazé
Global optimization and monotonicity in entropy production of weak drivings
Pierre Nazé