A Milne problem from a Bose condensate with excitations

Artikel i vetenskaplig tidskrift, 2013

The paper deals with a half-space linearized problem for the distribution function of the excitations in a Bose gas close to equilibrium. Existence and uniqueness of the solution, as well as its asymptotic properties are proven for a given energy flow. The problem differs from the ones for classical Boltzmann and related equations, where the hydrodynamic mass flow along the half-line is constant. Here ist is no more constant. Omstead we use energy flow which is constant but no more hydrodynamic.