Hidden and explicit quantum scale invariance | Sander Mooij (EPFL, Switzerland)

Abstract:

SCALE INVARIANCE: CLASSICAL OR QUANTUM, HIDDEN OR EXPLICIT

At the classical level, knowledge of a theory's Lagrangian is enough to establish whether it is scale invariant or not. At the quantum level, one also needs a prescription for the regularisation and renormalisation of that theory. The most famous regularisation schemes, such as dimensional regularisation (DR), break scale invariance. We show an alternative, scale independent, regularisation scheme. We also show how a theory can have ''hidden" scale invariance: we propose a scale dependent classical theory which after dimensional regularisation (also scale dependent) generates a scale independent quantum theory.