Three-form lifting of dilaton flat direction without and with gravity

Abstract

Spontaneous scale symmetry breaking is commonly associated with a flat direction in the action. We show that this need not be so if the dilaton is coupled to a three-form field in a manner compatible with gauge invariance and dilatations. The resulting effective dynamics lifts the flat direction without introducing explicit scale-violating operators. When gravity is included, the corresponding potential takes the form of an exponential plateau.

14 pages, no figures