Homotopy kinematic algebras at null infinity
Felipe Díaz-Jaramillo, Silvia Nagy, Giorgio Pizzolo
TL;DR
The paper addresses how to encode asymptotic data near null infinity within a homotopy-algebraic framework for gauge theories, focusing on self-dual Yang–Mills in Bondi coordinates. It introduces a $L_\infty$-based formulation compatible with a $1/r$ expansion, then derives a master system that yields physically correct fall-offs and a spectrum of slice-dependent kinematic algebras. By constructing projections and cochain maps, the authors produce an infinite family of sliced $L_\infty$ algebras and, through refinements, obtain several strict kinematic Lie algebras on refined slices; they also establish a quasi-isomorphism to the boundary theory. The results deepen the algebraic underpinning of color–kinematics duality and the double copy in the asymptotic regime and point toward extensions to gravity and BMS-like symmetries with potential implications for celestial holography and infrared structure.
Abstract
We present the first formulation of a homotopy algebra adapted to a $1/r$ expansion near future null infinity ($\mathcal{I^+}$). Focusing on self-dual Yang-Mills theory in Bondi coordinates, we demonstrate that imposing the homotopy algebra relations naturally yields the physically consistent fall-off behavior of the fields near $\mathcal{I^+}$. Furthermore, we employ this framework to systematically construct kinematic algebras, uncovering novel infinite families of such algebras that satisfy the Jacobi identity on slices near $\mathcal{I^+}$.
