A journey of composite defects
Organizers
Speaker
Dongsheng Ge
Time
Friday, March 20, 2026 4:00 PM - 5:30 PM
Venue
Shuangqing-B627
Online
Zoom 230 432 7880
(BIMSA)
Abstract
Composite defect Quantum Field Theory represents a new regime where analytical tools are still at hand, though spacetime symmetries are further broken by introducing a sub-defect inside a conventional defect system. We have constructed explicitly such a composite defect model in terms of $d=3-\epsilon$ vector $O(N)$ models via localized interactions. This model allows for unitary Wilson-Fisher fixed points and is shown perturbatively to satisfy a weak C-theorem for the subdefect along the localized RG flows. Through further studies, this model is found to be identical to a two-dimensional long-range Ising model with a pining type interface. Such a pining interface appears to be non-factorizing in the IR limit, as opposed to what the factorizing conjecture suggests. This talk is based on 2408.04428, 2505.15018 and ongoing works.
Speaker Intro
葛东胜博士于2020年在法国巴黎高等师范学院取得博士学位，之后分别在波兰华沙大学和日本大阪大学进行博士后研究工作，目前即将加入“数学科学中心”刘正伟教授课题组接续博士后研究。他的研究兴趣主要集中于缺陷量子场论，以及缺陷在全息量子引力以及量子信息中的应用。