| Abstract: | In this paper, we present details of the physics of cosmic γ-ray production by the annihilation of dark matter particles and cosmological antimatter. For the latter process, considerations of γ-ray absorption and scattering at high redshifts is important and we review the physics of these processes also. Cosmic γ-ray spectra are calculated and presented and compared with present observational data on cosmic γ-ray fluxes at high galactic latitudes. A comparison with the γ-ray flux from cosmic-ray interactions is made and the observability of annihilation γ-rays is considered. |
