The paper considers a modified spatially homogeneous Boltzmann equation for
Fermi Dirac particles (BFD). We prove that for the BFD equation there are
only two classes of equilibria: the first ones are Fermi Dirac distribution
s, the second ones are characteristic functions of the Euclidean balls, and
they can be simply classified in terms of temperatures: T > 2/5 T-F and T
= 2/5 T-F, where T-F denotes the Fermi temperature. In general we show that
the L-infinity-bound 0 less than or equal to f less than or equal to 1/eps
ilon derived from the equation for solutions implies the temperature inequa
lity T greater than or equal to 2/5 T-F and if T > 2/5 T-F, then f trend to
wards Fermi Dirac distributions; if T = 2/5 T-F, then f are the second equi
libria. In order to study the long-time behavior, we also prove the conserv
ation of energy and the entropy identity, and establish the moment producti
on estimates for hard potentials.