Cosmological-constant domination ($H^2\simeq \Lambda c^2/3$)

An expanding-universe regime in which a positive cosmological constant supplies most of the Friedmann equation. The approximately constant positive expansion rate gives exponential growth of the scale factor. Since matter, radiation, and curvature contributions decay with expansion, a positive cosmological constant eventually dominates a perpetually expanding model containing them; this does not guarantee that curvature dominates at an intermediate time.