Executive Summary : | Infra-red structure of quantum gravity predicts Ward identities for a two dimensional conformal field theory on the celestial sphere of Minkowski space-time. Celestial holography is a proposal for calculating scattering amplitudes of gravitons and other gauge mediators in Minkoski space-time through the correlation functions of conformal field theory living at the boundary celestial sphere. Further developments require the dual conformal field theory to be dynamical along the null time of the null boundary as well. This null surface has degenerate metric and requires caution while defining dynamics on that. A special class of quantum field theories, namely Carrollian ones, satisfy this stringent requirement, as well as obeying the symmetry constraints. The present project aims to strengthen the celestial holography proposal by finding interacting candidate field theories, checking Ward identities explicitly on the asymptotic null boundary of asymptotically flat space time, which will help calculating and succinctly arranging bulk scattering amplitudes. The present project involving three dimensional Carrollian conformal field theories would usher towards loop level corrections of the scattering amplitudes. |