Soft Limits of Yang-Mills Amplitudes and Conformal Correlators

Abstract

We study tree-level celestial amplitudes in Yang-Mills theory -- Mellin transforms of multi-gluon scattering amplitudes that convert them into the correlators of conformal primary fields on two-dimensional celestial sphere. By using purely field-theoretical methods, we show that the soft conformal limit of celestial amplitudes, in which one of the primary field operators associated to gauge bosons becomes a dimension one current, is dominated by the contributions of low-energy soft particles. This result confirms conclusions reached by using Yang-Mills theory formulated in curvilinear coordinates, as pioneered by Strominger. By using well-known collinear limits of Yang-Mills amplitudes, we derive the OPE rules for the primary fields and the holomorphic currents arising in the conformally soft limit. The Ward identities following from OPE have the same form as the identities derived by using soft theorems.

16 pages. v2: 1 reference added

References in corpus (2)

• Low's Subleading Soft Theorem as a Symmetry of QED
• 4D Scattering Amplitudes and Asymptotic Symmetries from 2D CFT

Cited by in corpus (8)

• Carrollian Perspective on Celestial Holography
• Bridging Carrollian and Celestial Holography
• The SAGEX Review on Scattering Amplitudes, Chapter 11: Soft Theorems and Celestial Amplitudes
• Supersymmetric celestial OPEs and soft algebras from the ambitwistor string worldsheet
• $p$-Forms on the Celestial Sphere
• Dynamical Edge Modes in Yang-Mills Theory
• Asymptotic Higher Spin Symmetries III: Noether Realization in Yang-Mills Theory
• Non-abelian soft radiation data for a celestial theory