  A nonlocal quantum gravity theory is presented which is finite and unitary to
all orders of perturbation theory. Vertex form factors in Feynman diagrams
involving gravitons suppress graviton and matter vacuum fluctuation loops by
introducing a low-energy gravitational scale, \Lambda_{Gvac} < 2.4\times
10^{-3} eV. Gravitons coupled to non-vacuum matter loops and matter tree graphs
are controlled by a vertex form factor with the energy scale, \Lambda_{GM} <
1-10 TeV.
