  Celestial holography proposes a duality between the gravitational
$\mathcal{S}$-matrix and correlators in a conformal field theory living on the
celestial sphere. In this white paper, solicited for the 2022 Snowmass process,
we review the motivation from asymptotic symmetries, fundamentals of the
proposed holographic dictionary, potential applications to experiment and
theory, and some important open questions.
