Gravitational Reconstruction in $AdS_{4}$

Abstract

We reconstruct linearized gravitational perturbations in $AdS_{4}$ from a conserved, traceless stress tensor on a fixed conformally flat boundary metric, extending our earlier real Lorentzian construction. For admissible data with no spacelike Fourier support in a flat conformal frame, the physical response reduces to an integral over boundary light-cone cuts. Boundary improvements restore Fefferman--Graham (FG) gauge while preserving normalizability and the linearized Weyl tensor. We then reconstruct perturbations with general spacelike boundary momentum, including nonzero frequency and its zero-frequency limit, using explicit position-space generalized functions on real stress data. Boundary kernels are constructed for normalizable perturbations and sufficient conditions are derived for the reconstruction to converge. The results motivate controlled flat-space limits relevant to Bondi--Metzner--Sachs symmetries and celestial holography.