2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/35478We examine the dependence of decoherence on the spectral density of the environment as well as on the initial state of the system. We use two simple examples to illustrate some important effects. The simplest derivation of the general form of the master equation for a general quantum Brownian motion is outlined in an Appendix.14 Pages, 2 Figures available upon request, Preprint LA-UR-92-878, to appear in ``The Physical Origins of Time Asymmetry'' ed by J.J. Halliwell et al., Cambridge Univ. PressGeneral Relativity and Quantum CosmologyHigh Energy Physics - Theorytext