Introduction to Nonextensive Statistical Mechanics and Thermodynamics

Original · EN

In this lecture we briefly review the definition, consequences and applications of an entropy, Sq, which generalizes the usual Boltzmann-Gibbs entropy SBG (S₁=SBG), basis of the usual statistical mechanics, well known to be applicable whenever ergodicity is satisfied at the microscopic dynamical level. Such entropy Sq is based on the notion of q-exponential and presents properties not shared by other available alternative generalizations of SBG. The thermodynamics proposed in this way is generically nonextensive in a sense that will be qualified. The present framework seems to describe quite well a vast class of natural and artificial systems which are not ergodic nor close to it. The a priori calculation of q is necessary to complete the theory and we present some models where this has already been achieved.