English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

One of the methods to calculate tree-level multi-gluon scattering amplitudesis to use the Berends-Giele recursion relation involving off-shell currents oroff-shell amplitudes, if working in the light cone gauge. As shown in recentworks using the light-front perturbation theory, solutions to these recursionsnaturally collapse into gauge invariant and gauge-dependent components, atleast for some helicity configurations. In this work, we show that suchstructure is helicity independent and emerges from analytic properties ofmatrix elements of Wilson line operators, where the slope of the straight gaugepath is shifted in a certain complex direction. This is similar to theprocedure leading to the Britto-Cachazo-Feng-Witten (BCFW) recursion, howeverwe apply a complex shift to the Wilson line slope instead of the externalmomenta. While in the original BCFW procedure the boundary integrals over thecomplex shift vanish for certain deformations, here they are non-zero and areequal to the off-shell amplitudes. The main result can thus be summarized asfollows: we derive a decomposition of a helicity-fixed off-shell current intogauge invariant component given by a matrix element of a straight Wilson lineplus a reminder given by a sum of products of gauge invariant and gaugedependent quantities. We give several examples realizing this relation,including the five-point next-to-MHV helicity configuration.

Off-shell amplitudes as boundary integrals of analytically continued Wilson line slope