SEMINAIRE MERCREDI 7 JUIN 2006 14 heures Salle Séminaire 5 Centre de Physique Théorique Marseille-Luminy Jean Bellissard Georgia Institute of Technology, School of Mathematics and School of Physics, Atlanta GA, USA Title: On Quantum Transport Theory for Solids Abstract: Transport theory is a complex subject due to the interplay between several scales in time, length and/or energy. Few striking effects in Solids will be used as a motivation. We will review the heuristic leading to various approximations and to the formalism used in such a situation: the local equilibrium approximation, the Markov approximation, the adiabatic approximation. We will also give the heuristic derivation of the Green-Kubo formula for transport coefficients within the linear response theory. Then we will discuss various rigorous problem to be investigated and various results already obtained: existence of Markov semigroups for a large class of realistic models describing electrons on a lattice, one-to-one correspondence with XY-type quantum spin systems, classification of Markov semigroups on various types of C*-algebras. (work with R. Rebolledo, D. Spehner)