Abstract
Classically, the unimodular theory of gravity with a constrained determinant is equivalent to general relativity augmented by an arbitrary cosmological constant Λ, which arises as an integration constant. At the quantum level we argue that an integration over Λ should be included in the Euclidean path integral for the vacuum functional. The fully renormalized Λ=0 overwhelmingly dominates all other contributions yielding a zero observed cosmological constant. While the technical part of our argument is similar to that of the ‘‘wormhole’’ argument, the two approaches are logically different.
- Received 27 April 1990
DOI:https://doi.org/10.1103/PhysRevLett.65.1972
©1990 American Physical Society