Dilaton, conformal symmetry and Weyl invariance

Abstract

I’ll show how to implement spontaneous breaking of conformal symmetry at the quantum level from the IR perspective. In other words how to introduce consistently the (massless) dilaton. Given the importance of the Weyl invariance in the construction it is necessary to understand the relation between conformal symmetry and Weyl invariance. I’ll touch upon the issue and present examples of theories that are conformally invariant but do not admit Weyl invariant generalizations.