Nonperturbative evolution equation for quantum gravity
Abstract
A scaledependent effective action for gravity is introduced and an exact nonperturbative evolution equation is derived which governs its renormalization group flow. It is invariant under general coordinate transformations and satisfies modified BecchiRouetStora Ward identities. The evolution equation is solved for a simple truncation of the space of actions. In 2+∊ dimensions, nonperturbative corrections to the β function of Newton's constant are derived and its dependence on the cosmological constant is investigated. In 4 dimensions, Einstein gravity is found to be ``antiscreening'' i.e., Newton's constant increases at large distances.
 Publication:

Physical Review D
 Pub Date:
 January 1998
 DOI:
 10.1103/PhysRevD.57.971
 arXiv:
 arXiv:hepth/9605030
 Bibcode:
 1998PhRvD..57..971R
 Keywords:

 04.60.m;
 11.10.Hi;
 11.15.Tk;
 Quantum gravity;
 Renormalization group evolution of parameters;
 Other nonperturbative techniques;
 High Energy Physics  Theory;
 General Relativity and Quantum Cosmology
 EPrint:
 35 pages, latex