Microscopic explanation of non-Debye relaxation for heat transfer

We give a microscopic explanation of both Debye and non-Debye thermalization processes that have been recently reported by Gall and Kutner [Physica A 352 (2005) 347]. Due to reduction of the problem to first passage phenomena we argue that relaxation functions f(t) introduced by the authors directly correspond to survival probabilities S(t) of particles in the considered systems. We show that in the case of broken ergodicity (i.e., in the case of mirror collisions) the survival probability decays as a power law S(t)=τ/t.