张欣宇博士学术报告
Title: Tetrahedron Instantons
Speaker: Xinyu Zhang
Affiliation: Deutsches Elektronen-Synchrotron DESY
Time: 16:00-17:00, Tuesday, Feb 15th, 2022 (UTC+8, Beijing Time)
Venue: Zoom Meeting
Inviter: Wen Qiang
Abstract
We introduce and analyze tetrahedron instantons, which can be realized in string theory by D0-branes probing a configuration of intersecting D6-branes with a nonzero constant background B-field. Physically they capture instantons in six-dimensional gauge theories with the most general intersecting codimention-two supersymmetric defects. We study the properties of the moduli space of tetrahedron instantons. We compute the instanton partition function, which lies between the higher-rank Donaldson-Thomas invariants and the partition function of the magnificent four model. Remarkably the instanton partition function has a closed-form expression in terms of the plethystic exponential, and matches the index of M-theory on a Calabi-Yau fivefold. Our computations provide an equivariant test of the duality between M-theory and type IIA string theory.
About the Speaker
Dr. Xinyu Zhang is currently a Postdoctoral Fellow at DESY in Germany. He got his Ph.D. Degree under the supervision of Nikita Nekrasov at Stony Brook University in 2017 and then worked as a Postdoctoral Associate at the New High Energy Theory Center and Department of Physics and Astronomy at Rutgers University from September, 2017 to August, 2020. His research interests include quantum field theory, supersymmetry, string theory, and mathematical physics.
The seminar will be broadcasted online by Zoom.
Interested people are free to join, without registration in advance.
The Zoom info is
URL:https://us02web.zoom.us/j/3854420225?pwd=SXY4eWJKOTBFZWJDaE16aXpTamY1QT09
Meeting ID: 385 442 0225
Passcode: yauc
Zhang Xinyu-Tetrahedron Instantons 20220215 SEU(1).pdf