Hot Dark Matter

Hot dark matter is a type of dark matter that would be constituted by particles traveling at relativistic velocity. The most likely candidate for hot dark matter is the neutrino.

Neutrinos have an insignificant mass, have no electric charge and therefore practically do not interact with matter, which makes them incredibly difficult to detect. These same features are also what makes them good candidates for being hot dark matter.

Hot dark matter, however, can not explain how individual galaxies formed from the Big Bang. The background of microwave radiation as measured by the COBE satellite is uniform and can not be explained as fast moving particles would be added from this initial state. To explain the structure of the universe, cold dark matter becomes necessary. Hot dark matter is currently discussed as a part of the mixed theory of dark matter.

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