Speaker
Description
In critical phenomena, the presence of surfaces or more general boundaries gives rise to rich phase diagrams and interesting phenomena, such as critical adsorption and critical Casimir forces. Despite being a mature subject, boundary critical phenomena have recently attracted a renewed attention, driven in particular by the discovery of unexpected behavior in various quantum spin models, and by progresses in conformal field theory.
In this context, a reexamination of the simplest model of boundary criticality -- the three-dimensional O(N) model bounded by a bidimensional surface -- has led to the discovery of a hitherto overlooked boundary phase, the so-called extraordinary-log phase.
Beyond surfaces, other kind of extended defects, such as line defects, have been considered.
In this seminar I will give an introduction to the problem and review the recent advances, focusing in particular on results of numerical simulations, and discuss future research directions.
