Cosmology, Gravity, and the WMAP ratio 0.73:0.23:0.04

WMAP results indicate that our universe is now made up of 73% dark energy (DE), 23% dark matter (DM), and 4% ordinary matter (OM), the DE possibly being in the form of a cosmological constant (itself a misnomer, as a "cosmological constant" can be variable). A model of gravity based on the conformal group Spin(2,4) = SU(2,2), motivated by work of I. E. Segal, can be used to estimate the present-day DE : DM : OM ratio. If DM obeys the ordinary matter equation of state, then the model gives the ratio 0.753 : 0.202 : 0.045, which is quite close to the WMAP observation of 0.73 : 0.23 : 0.04.