Abstract: The Schur index of a 4d SCFT can be identified with the vacuum character of an associated chiral algebra. Similar to the characters of a rational chiral algebra, the Schur index is expected to enjoy certain modularity. In this talk we will derive for A_1 class-S theories and SU(N) N=4 theories the modular orbit and prove a dimension formula that predicts the minimal order of the unflavored modular differential equations that constrain the chiral algebra. We will also discuss the high temperature limit of the A₁ class-S Schur index with surface defects, and relate it to the Wilson line index of the 3d mirror dual theory.

主讲人简介：潘逸文，中山大学物理学院副教授。2010年于中山大学获得学士学位，2015年从纽约州立石溪大学获得物理学博士学位，之后在瑞典乌普萨拉大学从事博士后研究。研究方向是量子场论、数学物理，主要关注超对称共形场论、手征代数等问题。