Public Research Seminar by Center of Quantum Science and Technology, HKUST(GZ) - The Lefschetz thimble and its application to the spin foam model
The Lefschetz-thimble method is a way to evaluate the complex path integral in a system with complex-valued action. In this talk, two interesting applications of this method will be given: to compute the observables in the system suffering from the sign problem and to find the complex saddle points of an analytically continued action. In particular, the covariant formulation of the Loop Quantum Gravity, i.e., the spin foam model, is used as our proofing ground. We use the thimble method to compute 2-point correlation function and to find the complex saddle points in the spin foam model.
Zichang Huang got his B.S. from the Beijing Normal University in 2012. In 2013, he got the master’s degree from the Aix-Marseille University in France. After that he went to the Florida Atlantic University and got his Ph.D. in 2019. From 2019 to 2022, he worked in Fudan University as a post-doctoral researcher. Zichang works on the loop quantum gravity (LQG) which discusses how the gravity theory can be combined with the quantum theory. Specifically, he focused on using the numerical methods to solve problems in the LQG.