**
Below is the ascii version of the abstract for 03-56.
The html version should be ready soon.**Laszlo Erdos, Manfred Salmhofer, Horng-Tzer Yau
On the quantum Boltzmann equation
(35K, latex)
ABSTRACT. We give a nonrigorous derivation of the
nonlinear Boltzmann equation from the Schrodinger evolution of
interacting fermions. The argument is based mainly on the
assumption that a quasifree initial state satisfies a property
called restricted quasifreeness in the weak coupling limit
at any later time. By definition, a state is called restricted
quasifree if the four-point and the eight-point functions of the
state factorize in the same manner as in a quasifree state.