Abstract
The running of Newton’s constant can be taken into account by considering covariant, nonlocal generalizations of the field equations of general relativity. These generalizations involve nonanalytic functions of the d’Alembertian, as , with a noninteger number, and . In this paper we define these nonlocal operators in terms of the usual two point function of a massive field. We analyze some of their properties, and present specific calculations in flat and Robertson Walker spacetimes.
- Received 2 October 2006
DOI:https://doi.org/10.1103/PhysRevD.75.024003
©2007 American Physical Society