MERCREDI 30 SEPTEMBRE 2009
14 heures
Salle Séminaire 5
Centre de Physique Théorique
Marseille-Luminy

Massimo Materassi
Istituto dei Sistemi Complessi, CNR
Florence, Italie

Title: Aspects of Complexity in the Geospace Plasmas

Abstract: The definition of "complex system" adopted here is that of a
classical composite system, whose macroscopic quantities do not evolve
smoothly and deterministically as the equilibrium Statistical
Mechanics would predict. In this sense, the plasmas forming the
near-Earth space (i.e. the Geospace plasmas) are certainly complex
systems.

The main focus of the seminar is then to give a taste of how the study
of Geospace plasma phenomenology is a good playground to focus
non-trivial issues of Statistical Mechanics and to forge new
theoretical and data analysis tools to face them.

In particular, the problems addressed are those on which the speaker
is working at the Insitute for Complex Systems in Florence: a
"fractal" approach to the calculation of the magnetic reconnection
rate, a stochastic version of resistive magnetohydrodynamics, some
applications of information theory to the near-Earth plasma physics.