Fuzzy cold dark matter: The wave properties of ultralight particles

Cold dark matter (CDM) models predict small-scale structure in excess of ob servations of the cores and abundance of dwarf galaxies. These problems mig ht be solved, and the virtues of CDM models retained, even without postulat ing ad hoc dark matter particle or held interactions, if the dark matter is composed of ultralight scalar particles (m similar to 10(-22) eV), initial ly in a (cold) Bose-Einstein condensate, similar to axion dark matter model s. The wave properties of the dark matter stabilize gravitational collapse, providing halo cores and sharply suppressing small-scale linear power.