Defects and Interfaces in the O(N) Model @DIASDublin

Uploaded November 2024 | Updated September 2026, 2 weeks ago

Speaker: Sabine Harribey (DIAS)
Abstract: Introducing defects for O(N) critical models has recently sparked much interest. Indeed, from a theoretical point of view defects give rise to new universality classes of 3D CFTs that can often be studied analytically. Defects can also describe physical impurities or finite-size effects that can be realised experimentally. In this talk, I will first review line defects and surface defects in the O(N) model. I will then present another approach through interfaces with localised cubic interactions perturbing a quartic multi-scalar model. We computed the one-loop beta functions and then looked for fixed points both analytically and numerically for different bulk symmetries. We found a large landscape of fixed points breaking the bulk symmetry to various subgroups

Defects and Interfaces in the O(N) Model

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