Triangle Seminars
Monday, 27 Sep 2021
Description:
Boundaries and defects have been at the heart of crucial developments in theoretical physics in the last 20 years: holography (field theories could live at the boundary of a higher- dimensional gravitational theory), entanglement (the entangling surface can be treated as a defect), black holes (the horizon is a boundary), topological insulators and semi-metals (the topologically-protected massless modes live at the boundary), and non-local operators such as Wilson and ‘t Hooft lines (defects defined by appropriate boundary conditions). Additionally, many other areas have made major advances in recent years whose implications for quantum field theory with boundaries and defects have yet to be explored fully: the conformal bootstrap, dualities among (2+1)d quantum field theories, supersymmetric localization, integrability, and so on.
However, progress in these areas has largely been carried out by separated communities working in isolation from the others. This scientific program thus aims to bring together a diverse group of leading theorists interested in boundaries and defects in quantum field theory, from the formal/mathematical to the applied, to forge collaborations between different areas, identify common subjects and complementary approaches, and set the agenda for future developments and new applications. The three broad focus areas will be:
* Conformal field theories with boundaries and defects
* Supersymmetry and Duality with boundaries and defects
* Curved space, gravity and entanglement
Please register online in order to receive Zoom links.
Boundaries and defects have been at the heart of crucial developments in theoretical physics in the last 20 years: holography (field theories could live at the boundary of a higher- dimensional gravitational theory), entanglement (the entangling surface can be treated as a defect), black holes (the horizon is a boundary), topological insulators and semi-metals (the topologically-protected massless modes live at the boundary), and non-local operators such as Wilson and ‘t Hooft lines (defects defined by appropriate boundary conditions). Additionally, many other areas have made major advances in recent years whose implications for quantum field theory with boundaries and defects have yet to be explored fully: the conformal bootstrap, dualities among (2+1)d quantum field theories, supersymmetric localization, integrability, and so on.
However, progress in these areas has largely been carried out by separated communities working in isolation from the others. This scientific program thus aims to bring together a diverse group of leading theorists interested in boundaries and defects in quantum field theory, from the formal/mathematical to the applied, to forge collaborations between different areas, identify common subjects and complementary approaches, and set the agenda for future developments and new applications. The three broad focus areas will be:
* Conformal field theories with boundaries and defects
* Supersymmetry and Duality with boundaries and defects
* Curved space, gravity and entanglement
Please register online in order to receive Zoom links.
Posted by: m.buican@qmul.ac.uk
Wednesday, 29 Sep 2021
In search of fixed points in non-abelian gauge theories using perturbation theory
📍 London
Marco Serone
(SISSA, INFN Trieste)
Abstract:
Four-dimensional gauge theories can flow in the IR to non-trivial CFTs.
By employing Borel resummation techniques both to the ordinary perturbative series and to the Banks-Zaks conformal expansion, we first analyze the conformal window of QCD and find substantial evidence that QCD with n_f=12 flavours flows in the IR to a CFT.
We then study UV fixed points for SU(n_c) gauge theories with fundamental fermion matter in 4+2epsilon dimensions. Using resummation techniques similar to those used in the 4d QCD case, we provide evidence for the existence of non-supersymmetric CFTs in d=5 space-time dimensions in a certain range of colors and flavours.
Four-dimensional gauge theories can flow in the IR to non-trivial CFTs.
By employing Borel resummation techniques both to the ordinary perturbative series and to the Banks-Zaks conformal expansion, we first analyze the conformal window of QCD and find substantial evidence that QCD with n_f=12 flavours flows in the IR to a CFT.
We then study UV fixed points for SU(n_c) gauge theories with fundamental fermion matter in 4+2epsilon dimensions. Using resummation techniques similar to those used in the 4d QCD case, we provide evidence for the existence of non-supersymmetric CFTs in d=5 space-time dimensions in a certain range of colors and flavours.
Posted by: andrea