The structure of IR divergences in celestial gluon amplitudes

A bstract The all-loop resummation of SU( N ) gauge theory amplitudes is known to factorize into an IR-divergent (soft and collinear) factor and a finite (hard) piece. The divergent factor is universal, whereas the hard function is a process-dependent quantity. We prove that this factorization persi...

Full description

Saved in:
Bibliographic Details
Published in:The journal of high energy physics 2021-06, Vol.2021 (6), p.1-27, Article 171
Main Authors: González, Hernán A., Rojas, Francisco
Format: Article
Language:English
Subjects:
Amplitudes
Classical and Quantum Gravitation
Conformal Field Theory
Cusps
Elementary Particles
Field Theories in Lower Dimensions
Gauge theory
Gluons
High energy physics
Mellin transforms
Operators
Physics
Physics and Astronomy
Quantum Field Theories
Quantum Field Theory
Quantum Physics
Radiation
Regular Article - Theoretical Physics
Relativity Theory
Scattering Amplitudes
Spacetime
String Theory
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A bstract The all-loop resummation of SU( N ) gauge theory amplitudes is known to factorize into an IR-divergent (soft and collinear) factor and a finite (hard) piece. The divergent factor is universal, whereas the hard function is a process-dependent quantity. We prove that this factorization persists for the corresponding celestial amplitudes. Moreover, the soft/collinear factor becomes a scalar correlator of the product of renormalized Wilson lines defined in terms of celestial data. Their effect on the hard amplitude is a shift in the scaling dimensions by an infinite amount, proportional to the cusp anomalous dimension. This leads us to conclude that the celestial-IR-safe gluon amplitude corresponds to a expectation value of operators dressed with Wilson line primaries . These results hold for finite N . In the large N limit, we show that the soft/collinear correlator can be described in terms of vertex operators in a Coulomb gas of colored scalar primaries with nearest neighbor interactions. In the particular cases of four and five gluons in planar N = 4 SYM theory, where the hard factor is known to exponentiate, we establish that the Mellin transform converges in the UV thanks to the fact that the cusp anomalous dimension is a positive quantity. In other words, the very existence of the full celestial amplitude is owed to the positivity of the cusp anomalous dimension.
ISSN:1029-8479
1029-8479
DOI:10.1007/JHEP06(2021)171