Speaker
Gordon Semenoff
(University of British Columbia)
Description
We study an exotic phase of a cold, two-dimensional, N-component Fermi gas which exhibits dynamically broken approximate scale symmetry. We identify a particular weakly damped collective excitation as the dilaton, the pseudo-Goldstone boson associated with the broken approximate scale invariance. We argue that the symmetry breaking phase is stable for a range of parameters of the theory and there is a fluctuation induced first order quantum phase transition between the normal and the scale symmetry breaking phases. This system provides a concrete cold atoms example of the Coleman-Weinberg phenomenon of dynamical violation of scale symmetry as well as a quantum field theoretical system where the Higgs field is a dilaton.
Author
Gordon Semenoff
(University of British Columbia)
