A double copy for asymptotic symmetries in the self-dual sector
Miguel Campiglia, Silvia Nagy
TL;DR
The work presents a concrete double copy dictionary for symmetries of the self-dual sectors of Yang-Mills and gravity in the light-cone gauge, uncovering two infinite families tied to residual gravitational diffeomorphisms. It shows nonperturbative bulk double copy rules and a perturbative-to-nonlocal mapping in the YM sector that produce nontrivial gravitational symmetries, with a clear null-infinity realization. At null infinity, holomorphic YM large gauge transformations double copy to holomorphic supertranslations, while certain non-gauge YM transformations double copy to superrotations, revealing a rich structure linking bulk and boundary symmetries. The results extend the color-kinematics duality to an entire tower of asymptotic symmetries, with a symmetry-raising map commuting with the DC, suggesting a path toward broader applicability beyond self-duality and potentially informing celestial amplitude and memory-effect frameworks.
Abstract
We give a double copy construction for the symmetries of the self-dual sectors of Yang-Mills (YM) and gravity, in the light-cone formulation. We find an infinite set of double copy constructible symmetries. We focus on two families which correspond to the residual diffeomorphisms on the gravitational side. For the first one, we find novel non-perturbative double copy rules in the bulk. The second family has a more striking structure, as a non-perturbative gravitational symmetry is obtained from a perturbatively defined symmetry on the YM side. At null infinity, we find the YM origin of the subset of extended Bondi-Metzner-Sachs (BMS) symmetries that preserve the self-duality condition. In particular, holomorphic large gauge YM symmetries are double copied to holomorphic supertranslations. We also identify the single copy of superrotations with certain non-gauge YM transformations that to our knowledge have not been previously presented in the literature.
