In this talk, we study the motion of particles moving in a blackhole background that is a small perturbation of Schwarzschild or Kerr. We show some global chaotic dynamics occurs in the presence of small perturbations. The blackhole shadow as was observed by the Event Horizon Telesope (see the picture) plays a central role in the study. We show that the blackhole shadow admits a fine structure by KAM theory.  

Introduction: Dr. Jinxin Xue received his bachlor degree from Nanjing University in 2008 and the Ph.D. from University of Maryland at 2013. He was a Dickson Instructor at University of Chicago from 2013-2017, and joined YMSC in 2017. He works in the field of dynamical systems,mainly in various complicated dynamical behaviors such as chaotic and singular dynamics.