The Hubble constant and dark energy
  The Hubble Constant measured from the anisotropy in the cosmic microwave
background (CMB) is shown to be independent of small changes from the standard
model of the redshift dependence of dark energy. Modifications of the Friedmann
equation to include phantom power (w < -1), textures (w = -2/3) and curvature
are considered, and constraints on these dark energy contributors from
supernova observations are derived. Modified values for the density of matter
inferred from cosmic density perturbations and from the CMB under these
circumstances are also estimated, as exemplified by 2df and SDSS.
