In this talk, I will introduce a framework utilizing zero-dimensional defects to analyze light-light-heavy-heavy (LLHH) correlators in conformal field theories. I will apply this formalism specifically to giant graviton correlators in N=4 super Yang-Mills. By combining this defect perspective with analytic bootstrap techniques, I will show how we can completely determine infinitely many four-point correlators at strong coupling. Furthermore, I will highlight a partially broken, higher-dimensional hidden symmetry that packages these correlators into a single generating function which also persists at weak coupling. I will also explain how a systematic operator product expansion analysis allows us to extract nontrivial dynamical information, including the complete spectrum of anomalous dimensions for double-particle operators. Finally, I will demonstrate that this zero-dimensional defect formalism extends far beyond supersymmetry, providing a naturally nonperturbative description for LLHH correlators in any general CFT by reducing four-point conformal blocks to defect two-point blocks in the heavy limit.

Biography

Xinan Zhou is a faculty member at the Kavli Institute for Theoretical Sciences (UCAS) and the recipient of the 2023 ICTP Prize. His research focuses on high energy physics, particularly the AdS/CFT correspondence, conformal bootstrap, scattering amplitudes, and quantum gravity. He received his undergraduate degree from the University of Science and Technology of China and earned his PhD from the C. N. Yang Institute for Theoretical Physics at Stony Brook University in 2018. Prior to his current role, he was a postdoctoral fellow at the Princeton Center for Theoretical Science from 2018 to 2021.

Inviter: Song He