Hadronic structure on the light-front II: QCD strings, Wilson lines and potentials

TL;DR

This paper explores the light-front formulation of hadronic wave functions, focusing on confinement via QCD strings, Wilson line correlators, and instanton effects, advancing understanding of hadronic structure in quantum chromodynamics.

Contribution

It introduces a Hamiltonian approach incorporating confinement, Wilson lines, and instanton effects in the light-front framework, providing new tools for hadronic structure analysis.

Findings

Derived the light-front Hamiltonian for confinement effects

Analyzed Wilson line correlators leading to an effective Hamiltonian

Examined instanton-induced interactions related to pion formation

Abstract

This is the second paper on hadronic wave functions in the light front formulation. We first consider only confinement effects, using the classical Nambu-Gotto string with massive end points in the light cone gauge. We derive the light-front Hamiltonian and show how to solve it, using an expansion in suitable basis functions. We next discuss the correlators of Wilson lines on the light front, leading to an effective Hamiltonian that includes spin effects. At the end, we consider a separate problem of instanton-induced interactions, at the origin of the pion as a massless Goldstone mode on the light front.