Gauge invariant reduction to the light-front

TL;DR

This paper presents a method to construct gauge-invariant electromagnetic currents within the light-cone formalism, ensuring current conservation at each perturbative order, thus improving the theoretical consistency of light-front bound-state calculations.

Contribution

It introduces a systematic approach using the gauging of equations to achieve gauge invariance in light-front bound-state electromagnetic currents.

Findings

Constructed gauge-invariant currents in light-cone formalism.

Ensured current conservation at all perturbative orders.

Provided a framework for consistent light-front calculations.

Abstract

The problem of constructing gauge invariant currents in terms of light-cone bound-state wave functions is solved by utilising the gauging of equations method. In particular, it is shown how to construct perturbative expansions of the electromagnetic current in the light-cone formalism, such that current conservation is satisfied at each order of the perturbation theory.