Reversible Limits of Large Systems of Particles

Several approximation for large
system of particles turn out to be at variance with what happens for Boltzmann
equations, reversible.

This correspond to the mean field scaling and this appears both at
the classical and quantum level.

Several basic examples will be described. The classical Vlasov limit
(with a $C^2$ potentiaal) of classical Newtonian dynammic and the Hartree or Hartree
Fock approximation for quantum dynamic.