Reparametrization mode and chaos on the worldsheet


Komatsu, S. (2023). Reparametrization mode and chaos on the worldsheet. Perimeter Institute. https://pirsa.org/23020048


Komatsu, Shota. Reparametrization mode and chaos on the worldsheet. Perimeter Institute, Feb. 14, 2023, https://pirsa.org/23020048


          @misc{ pirsa_23020048,
            doi = {10.48660/23020048},
            url = {https://pirsa.org/23020048},
            author = {Komatsu, Shota},
            keywords = {Quantum Fields and Strings},
            language = {en},
            title = {Reparametrization mode and chaos on the worldsheet},
            publisher = {Perimeter Institute},
            year = {2023},
            month = {feb},
            note = {PIRSA:23020048 see, \url{https://pirsa.org}}

Shota Komatsu Princeton University


The path integral over reparametrization modes in one dimension played an important role in the duality between JT gravity and the SYK model. In this talk, I will explain that the reparametrization modes are important also in certain computations involving the string worldsheet with boundaries. A few cases in which it is expected to play a crucial role are the Wilson loop expectation value in confining string, open strings with massive endpoints, and the string dual to the half-BPS Wilson loop in N=4 supersymmetric Yang-Mills. After reviewing these cases briefly, I will focus on the last case and explain how to compute the correlation function on the BPS Wilson loop from the string worldsheet in the conformal gauge. In particular, I will show that the inclusion of the reparametrization modes is crucial for reproducing the answer obtained previously in the static gauge. I will then use the reparametrization mode path integral to study the four-point functions in the out-of-time-ordered configuration and obtain an exact answer in a double-scaling regime interpolating between the Lyapunov regime and the late-time exponential decay. Interestingly the result has exactly the same functional form as in JT gravity although the actions for the reparametrization modes are different.

Zoom link:  https://pitp.zoom.us/j/99063427266?pwd=aG5iTlczNWhxdE9xNEZoVTlMSnVOQT09