Quantum Weyl Invariance and Cosmology
  Equations for cosmological evolution are formulated in a Weyl invariant
formalism to take into account possible Weyl anomalies. Near two dimensions,
the renormalized cosmological term leads to a nonlocal energy-momentum tensor
and a slowly decaying vacuum energy. A natural generalization to four
dimensions implies a quantum modification of Einstein field equations at long
distances. It offers a new perspective on time-dependence of couplings and
naturalness with potentially far-reaching consequences for the cosmological
constant problem, inflation, and dark energy.
