It has been recently shown that the quantum Boltzmann equations may be
relevant for the leptogenesis scenario. In particular, they lead to a
time-dependent CP asymmetry which depends upon the previous dynamics of the
system. This memory effect in the CP asymmetry is particularly important in
resonant leptogenesis where the asymmetry is generated by the decays of nearly
mass-degenerate right-handed neutrinos. We study the impact of the nontrivial
time evolution of the CP asymmetry in resonant leptogenesis, both in the
one-flavour case and with flavour effects included. We show that significant
qualitative and quantitative differences arise with respect to the case in
which the time dependence of the CP asymmetry is neglected.Comment: 16 pages, 7 figures. IOP LaTeX class used. Minor corrections and
references added. Matches the version published in JCA
