学术报告
题目: [理论室报告] A 2D-CFT Factory: Critical Lattice Models from Competing Anyon Condensation in SymTO
时间: 2025年10月24日 09:30
报告人: 万义顿

复旦大学物理系教授

摘要:

In this talk, we shall introduce a CFT factory -- a novel algorithm of methodically generating 2D lattice models that would flow to conformal field theories (CFTs) in the infrared. We realise these models by engineering the boundary conditions of 3D topological orders (SymTOs) described by string-net models. The critical points are induced by a commensurate condensation of non-commuting anyons. Our structured method generates an infinite family of critical lattice models, including the A-series minimal models, and uncovers previously unknown critical points. Notably, we discover at least three novel CFTs (with central charge c around 1.3, 1.8, and 2.5) that preserves the Haagerup symmetries, in addition to recovering previously reported examples. The non-invertible symmetries preserved at these points are dictated by a novel "refined condensation tree". The condensation trees predict large swathes of phase boundaries and sieves out second order phase transitions. This predictive power is illustrated not only in well-studied examples, such as the 8-vertex model associated with the A5 category, but also in new cases involving Haagerup symmetries, validated by an improved symmetry-preserving tensor-network renormalization group method. The critical couplings are precisely encoded in algebraic data (the Frobenius algebras and quantum dimensions of unitary fusion categories), thereby establishing a powerful and systematic route to the discovery and potential classification of new CFTs.

报告人简介:

Yidun Wan is a tenured professor of physics at Fudan University. He has a diverse educational background, with bachelor degrees in computer science and economics from South China University of Technology (1998), master of computer science from University of Pennsylvania (2002), master of physics from University of Ottawa (2004), and PhD in theoretical physics from University of Waterloo and Perimeter Institute for Theoretical Physics (2009). He also did postdoctoral research at Kinki University, Tokyo University, and Perimeter Institute for Theoretical Physics from 2009 to 2016. He joined Fudan as a professor in 2016. His research interests include cosmology, topological orders, quantum information and computation, and their interdisciplinary studies.

主持人:曹俊鹏

    junpengcao@iphy.ac.cn

地点:M楼837