Quantum Cosmology Near Two Dimensions
  We consider a Weyl-invariant formulation of gravity with a cosmological
constant in d-dimensional spacetime and show that near two dimensions the
classical action reduces to the timelike Liouville action. We show that the
renormalized cosmological term leads to a nonlocal quantum momentum tensor
which satisfies theWard identities in a nontrivial way. The resulting evolution
equations for an isotropic, homogeneous universe lead to a slowly decaying
vacuum energy and a power-law expansion. We outline the implications for the
cosmological constant problem, inflation, and dark energy.
