based on galactic rotation curves and cluster dynamics, we think dark matter based on galactic rotation curves and cluster dynamics, we think dark matter will have no effect on the fate of the universe. comprises over 90% of the entire mass of the universe. will doom the universe to collapse, overcoming the redshifts we now observe. is a minor component of the entire mass of the universe. is best detected from the x-rays it produces in the intergalactic medium.