From confinement to dark energy

The infrared divergence of the self-energy of a color charge is due to an enhancement of the long wavelength modes of the color Coulomb potential field. There are also long wavelength contributions to the QCD vacuum energy that are similarly enhanced. Vacuum modes of Hubble scale wavelengths may be affected in a cosmological setting and this can lead to a residual positive energy density of the form HdΛQCD4−d. Lattice studies constrain d. If the dark energy takes this form then the universe is driven towards de Sitter expansion, and we briefly study this cosmology when d is just slightly above unity.