1:30 pm VIA ZOOM
Worldsheet g-function and AdS/CFT.
Recently there has been new progress in computing a variety of observables in N=4 supersymmetric Yang-Mills theory in four dimensions at finite 't Hooft coupling, ranging from the correlation functions of "baryonic" operators to the instanton effects at large N. All those examples share three common features: 1. At weak coupling, they are given by overlaps between a matrix product state and an eigenstate of the Hamiltonian in integrable 1+1d spin chains. 2. Under the AdS/CFT correspondence, they can be mapped to the so-called g-functions on the string worldsheet, introduced originally by Affleck and Ludwig. 3. Thanks to the development of integrability techniques in the past decade, we can compute it exactly at finite coupling using the framework of thermodynamic Bethe ansatz. After explaining the basic ideas, I will showcase several applications.