The structure of IR divergences in celestial gluon amplitudes
Gonzalez
H
author
Rojas
F
author
2021
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.
Conformal Field Theory
Scattering Amplitudes
Field Theories in Lower Dimensions
WOS:000671162900001
exported from refbase (show.php?record=1436), last updated on Thu, 22 Jul 2021 19:39:25 -0400
text
10.1007/JHEP06(2021)171
Gonzalez+Rojas2021
Journal Of High Energy Physics
J. High Energy Phys.
2021
continuing
periodical
academic journal
6
171
1029-8479