In this talk I will explore the possibility that dark matter particles may come in mass-degenerate multiplets. A trivial consequence of this multiplicity are N-factors in dark matter cross sections which have non-trivial implications for dark matter searches.
If dark matter multiplicity arises from a weakly coupled non-Abelian dark gauge group the corresponding "dark gluons" can have interesting signatures in cosmology which I will review: 1. the "dark gluons" contribute to the radiation content of the universe and 2. gluon interactions with the dark matter may explain the >3 sigma discrepancy between precision fits to the CMB from Planck and direct measurements of large scale structure in the universe.
