Organizer

数学物理团队

Speaker

Kaiwen Sun 孙凯文

University of Science and Technology of China

Time

Thursday, 13:30 - 14:30

April 9, 2026

Venue

B627, Shuangqing Complex Building

2d Conformal Field Theories on Magic Triangle

The magic triangle due to Cvitanovic and Deligne-Gross is an extension of the Freudenthal-Tits magic square of semisimple Lie algebras. In a recent work with Kimyeong Lee, we identify all 2d rational conformal field theories associated to the magic triangle. These include various Wess-Zumino-Witten models, Virasoro minimal models, compact bosons and their non-diagonal modular invariants. At level one, we find a two-parameter family of modular linear differential equation of fourth order whose solutions produce the affine characters of all elements in the magic triangle. We find a universal coset relation for the whole triangle which generalizes the dual pairs with respect to (E8)_1 in the Cvitanovic-Deligne exceptional series. At level two, we find a special row of the triangle - the subexceptional series has novel N=1 supersymmetry, and the super characters satisfy a one-parameter family of fermionic modular linear differential equations. Moreover, we find many new coset constructions involving WZW models at higher levels.

About the Speaker:

孙凯文，中国科学技术大学数学科学学院特任研究员。2020年博士毕业于意大利国际高等研究院，曾先后在德国波恩马克斯普朗克数学研究所，韩国高等研究院，瑞典乌普萨拉大学从事博士后研究工作，2024年入职中科大。研究方向为数学物理，包括拓扑弦，超对称场论，共形场论等。