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.