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Extensions of topological symmetries

组织者

白岸斯 , 陈群皓 , 孔良 , 王亦龙 , 张智浩 , 郑浩

演讲者

Ingo Runkel

时间

2026年04月21日 16:00 至 17:30

地点

A6-101

线上

Zoom 361 038 6975 (BIMSA)

摘要

Topological defects play a key role in understanding properties of quantum field theories, such as dualities or renormalisation group flows. One can ask if there is a larger class of defects which share some of the good properties of topological defects, and which can be thought of as an extension of topological symmetries. Two-dimensional conformal field theory is a natural laboratory for such questions, and indeed one finds that translation invariant defects form such a larger class. These contain topological line defects and they still allow for a non-singular fusion operation. They still form a tensor category, which, however, is no longer fusion, as it is non-semisimple and possesses infinitely many simple objects. In this talk I want to present some properties of this larger class of defects and give an applications defect renormalisation group flows. This is joint work with Federico Ambrosino, Anatoly Konechny, and Gérard Watts.