Ph.D 2024

This thesis explores the derivation of chiral current algebras from different gravita-
tional theories, including R1,3 gravity, AdS4 gravity, and 3d conformal gravity. We
propose chiral boundary conditions consistent with the variational principle for 4d
asymptotically flat solutions yielding a chiral bms4 asymptotic symmetry algebra.
This symmetry algebra was earlier discovered in the context of celestial conformal
field theory. It is an infinite-dimensional chiral extension of the Poincaré algebra and
includes a copy of Virasoro algebra, a copy of sl(2, R) current algebra, and a doublet
of commuting currents with conformal weight h = 23 . Additionally, a novel non-chiral
infinite-dimensional symmetry algebra for R1,3 gravity is introduced through alterna-
tive non-chiral boundary conditions, considering the boundary metric in conformal
gauge.