During the semester we have a high energy seminar and a lunch seminar. In addition to these two seminars we participate in a joint theoretical high energy theory seminar in Newe Shalom. The joint seminar takes place on Tuesdays from 10:30 until 13:30 and includes two talks and lunch. This seminar is attended by the high energy groups of all the Israeli institutions and usually attracts a crowd of roughly twenty participants.
Sun Mon Tue Wed Thu Fri Sat
Title: Conformal operators in SYK-like models and their numerical effects
Abstract: Quantum mechanical models with random interactions have an infinite number of bilinear operators, the scaling dimensions of which can be computed explicitly in the large N limit. The lowest dimension operators play an important role in thermodynamical properties of these models and define the behavior of various correlation functions in the infrared limit. In this talk I’ll show that some SYK-like models have operators with unusual anomalous dimensions. I also demonstrate how they can be observed in numerical computations.
Based on works with Maria Tikhanovskaya, Haoyu Guo and Subir Sachdev
Title: Magnetic Quivers, Phase Diagrams, and Physics at Strongly Coupled Quantum Field Theories
Abstract: Quiver gauge theories experienced a breakthrough in activity through two important concepts, called “magnetic quivers” and “Hasse (phase) diagrams”. The first helps understanding the physics of strongly coupled gauge theories and exotic theories with tensionless strings in 6d or with massless gauge instants in 5d. The second gives an invaluable information about the phase structure of gauge theories, in analogy with phases of water. The talk will review these developments and explain their significance.
Title: Some aspects of line defects in d dimensions
Abstract: We consider renormalization group flows on line defects in d dimensions. We define a “defect entropy” and argue that it decreases monotonically during RG flows. We apply this result to line defects which appear in condensed matter and high energy physics, including magnetic (SPT) defects, localized field defects, and Wilson loops. In some of these cases we make some new experimental predictions and in the case of Wilson lines we make some comparisons with localization and holography.
Title: Automorphic Spectra and the Conformal Bootstrap
Abstract: I will explain that the spectral geometry of hyperbolic manifolds provides a remarkably faithful model of the modern conformal bootstrap. In particular, to each hyperbolic manifold, one can associate a Hilbert space of local operators, which is a unitary representation of a conformal group. The scaling dimensions of the operators are related to the eigenvalues of the Laplacian on the manifold. The operators satisfy an operator product expansion. Finally, one can define their correlation functions and derive bootstrap equations constraining the spectrum. As an application, I will use conformal bootstrap techniques to derive upper bounds on the lowest positive eigenvalue of the Laplacian on closed hyperbolic surfaces and 2-orbifolds. In a number of notable cases, the bounds are nearly saturated by known surfaces and orbifolds. For instance, the bound on all genus-2 surfaces is λ1≤3.8388976481, while the Bolza surface has λ1≈3.838887258. The talk will be based on https://arxiv.org/abs/2111.12716, which is joint work with P. Kravchuk and S. Pal.