BIMSA > Geometry and Physics Seminar 2021 Fall Celestial OPEs: from string worldsheet to infinite Ward identities
Celestial OPEs: from string worldsheet to infinite Ward identities
Organizer
Chi Ming Chang
Speaker
Hongliang Jiang
Time
Tuesday, November 23, 2021 4:00 PM - 5:30 PM
Venue
1120
Online
Zoom 810 537 7122 (ymscstring)
Abstract
Celestial holography reformulates the scattering amplitude holographically in terms of celestial conformal field theory living at boundary null infinity, thus opening up an interesting and promising avenue towards flat holography.  In particular, celestial operator product expansions (OPEs) arise from the collinear limit of scattering amplitudes and play a vital role in celestial holography. In this talk, I will discuss the celestial OPE and its implications from three different perspectives, the bulk scattering amplitude, the celestial conformal field theory, and the string worldsheet. More specifically, I will show how to derive the celestial OPEs from the string worldsheet OPEs. Then, I will focus on the soft sector of the celestial OPEs and derive an infinite-dimensional symmetry algebra, dubbed holography chiral algebra, in supersymmetric Einstein-Yang-Mills theory. These infinite symmetries give rise to infinite Ward identities in celestial CFT, which are equivalent to infinite soft theorems in scattering amplitudes.