何东洺  博士学术报告

Title: Lagrangian One-Point Functions in N =4 SYM with Boundaries and Defects

Speaker: Dongming He (何东洺)

Affiliation: Beijing Institute of Mathematical Sciences and Applications（北京雁栖湖应用数学研究所）

Time: 16:00-17:00, Thursday, 15th October, 2026 (UTC+8, Beijing Time)

Venue: Room 1502, Shing-Tung Yau Center, Sipailou Campus of Southeast University（东南大学四牌楼校区丘成桐中心1502室）

Inviter: Yunfeng Jiang (江云峰)

Abstract

One-point functions are among the simplest observables in quantum field theories with boundaries, defects, and interfaces, yet their dependence on the coupling can contain non-trivial dynamical information.

In this talk, I will discuss one-point functions of the ambient Lagrangian in $\mathcal N$=4 SYM with supersymmetric boundaries, defects, and interfaces. Using supersymmetric localization, we obtain these one-point functions for a broad class of Gaiotto–Witten theories and compare them with holographic calculations. For Janus interfaces, we obtain exact results and confirm a non-renormalization property, while theories with genuine defect degrees of freedom generally exhibit non-trivial coupling dependence. I will also comment on Janus interfaces with reduced supersymmetry. This talk is based on arXiv:2609.09303.

Speaker

Dongming He (何东洺) is a postdoctoral researcher at the Beijing Institute of Mathematical Sciences and Applications (BIMSA). He completed his PhD in 2026 at Vrije Universiteit Brussel under the supervision of Prof. Ben Craps and Prof. Christoph Uhlemann. Before that, he received his bachelor's degree from University of Science and Technology of China and his master's degree from University of Amsterdam. His research focuses on boundaries and defects in AdS/CFT and applications of supersymmetric localization.