Conformal QED3 and the epsilon expansion
- Event time: 2:00pm
- Event date: 7th September 2016
- Speaker: Emmanuel Stamou (Weizmann Institute)
- Location: Higgs Centre Seminar Room, James Clerk Maxwell Building (JCMB) James Clerk Maxwell Building Peter Guthrie Tait Road Edinburgh EH9 3FD GB
The theory of Quantum Electrodynamics in three dimensions (QED3) has received considerable attention due to its applications in condensed matter physics and due to its similarities with stongly coupled QCD-like theories in four dimensions. QED3 is strongly coupled at energies close to the gauge coupling that in this case is dimensionfull. Whereas for a large number of fermions the theory appears to be conformal in the IR, it is far from clear whether the conformal phase endures also for small numbers of fermions. In this talk I discuss a new mechanism that may provide the necessary dynamics to induce the departure from conformality. The renormalisation group flow generates a large scaling dimension to irrelevant operator making them dangerously relevant. In turn, their condesation may break the global symmetry of QED3 thus triggering the departure from conformality. I attempt to quantitatively access the mechanism using the epsilon-expansion at one- and two-loop order.
The Particle Physics Theory seminar is a weekly series of talks reflecting the diverse interests of the group. Topics include analytic and numerical calculations based on the Standard Model of elementary particle physics, theories exploring new physics, as well as more formal developments in gauge theories and gravity..