  We consider the quantum many-body evolution of a homogeneous Fermi gas in
three dimensions in the mean-field scaling regime. We study a class of initial
data describing collective particle-hole pair excitations on the Fermi ball.
Using a rigorous version of bosonization for non-solvable models, we prove that
the many-body evolution can be approximated in Fock space norm by a quasifree
bosonic evolution of the collective particle-hole excitations.
