Ricerc@Sapienza

The Statistical thermodynamics is the usual theory for the description of systems with a huge number of degrees of freedom. In recent times, under the challenges posed by nanotechnologies and by the interest for biological processes at the cellular level, there have been remarkable developments devoted to the statistical treatment of small systems. In these systems the relevant variables are subjected to strong fluctuations and, moreover, the systems are usually far from equilibrium.
The extension of the methods of statistical thermodynamics to these systems is not straightforward. For example, at difference with huge systems in equilibrium, in small non equilibrium systems all variables fluctuates, therefore already the selection of the relevant variables can be problematic.
In a search for an unified theoretical framework for the description of non equilibrium features of stochastic dynamical systems different fluctuation theorems have been developed. These can be formulated in terms of entropy production or information flows. The concept of information is at the heart of modern integrative biophysics and non equilibrium thermodynamics.