Alladi Ramakrishnan Hall

Fluctuation relations for entropy and work in small systems

Sourabh Lahiri

ESPCI, Paris

The fluctuation theorems (FTs) constitute some exact relations
in the field of nonequilibrium statistical physics, that remain valid even
when the system is driven far away from equilibrium. These relations not
only help in understanding the thermodynamic second law better, but are
also useful in practical applications like extracting information about the
change in equilibrium free energy even when the process is a nonequilibrium
one. These theorems have been extensively studied in the last two decades,
both in the presence as well as absence of feedback-controlled drives
acting on the system. In this talk, a basic introduction to the fluctuation
theorems and stochastic thermodynamics would be provided, followed by the
discussion of entropy production FT in transient regime and fraction of
events that apparently violate the second law. Consequences of application
of feedback to the system would be outlined. At the end, the calculation of
free energy change in presence of measurement noise will be discussed