Weakly Interacting Massive Particles (see also their nemises, MACHOs) A broad class of particles which were once in thermal equilibrium with the early universe but were "cold," i e , moving non-relativistically at the time of structure formation If the dark matter is composed mainly of WIMPs, then their density today is determined roughly by their annihilation rate, with weak-scale interactions WIMPs are expected to have collapsed into a roughly isothermal, spherical halo within which the visible portion of our galaxy resides, consistent with mesurements of spiral galaxy rotation curves The original WIMP was simply a heavy Dirac neutrino, now experimentally ruled out The neutralino predicted by supersymmetric extensions of the Standard Model is everyone's favorite WIMP nowadays This may be due to its non-ad hoc qualities: it is predicted in a separate context (particle physics) and actively sought in accelerator experiments, yet makes a nearly perfect cold dark matter particle
Dark matter jargon for Weakly Interacting Massive Particles; includes electrons, which have very little mass, and neutrinos, which may have zero mass Also called nonbaryonic matter