The Quantum Boltzmann Equation in a Nontrivial Background

This talk is a status report on our study of quantum transport equations relevant for baryogenesis computations. Our main finding is that, as a consequence of localization in space, the quasiparticle picture of the plasma dynamics breaks down at first non-trivial order in gradient expansion. While in this talk we focus on bosons, we expect that a similar picture holds for fermions. We then argue that the quasiparticle picture is recovered in the adiabatic limit of frequent scattering.