A new theoretical framework for computation of the relic abundance of cold
dark matter particles such as LSP is presented and some generic features of new
results are discussed. The most important is a generalization of the Boltzmann
equation to include off-shell effects and its thermal average over cosmic
medium. It is shown that at very low temperatures, much below the mass of
annihilating particles, equilibrium abundance is suppressed only by powers of
temperature instead of the exponential Boltzmann factor. This change gives a
larger relic abundance when heavy particles freeze out at these low
temperatures.Comment: 7 pages, LATEX file. Talk given at COSMO9
