Speaker
Prof.
Anna Stasto
(Penn State)
Description
In this presentation we will discuss some interesting properties of the off-shell scattering amplitudes in the framework of the light-front perturbation theory. It is shown that certain recursion relation between tree level off-shell amplitudes in this formalism actually resums whole classes of graphs into a Wilson line. More precisely, we demonstrate a correspondence between the light-front methods for the computation of the off-shell amplitudes and the approach which makes use of the matrix elements of straight infinite Wilson lines, which are manifestly gauge invariant objects and satisfy Ward identities. In addition, we demonstrate that such structure is helicity independent and emerges from analytic properties of matrix elements of Wilson line operators, where the slope of the straight gauge path is shifted in a certain complex direction. This is similar to the procedure leading to the Britto-Cachazo-Feng-Witten (BCFW) recursion, with the difference that a complex shift is applied to the Wilson line slope instead of the external momenta.
Primary author
Prof.
Anna Stasto
(Penn State)
Co-author
Piotr Kotko
(Institute of Nuclear Physics, PAN)
