Light-Front Quantization of Gauge Theories

TL;DR

This paper introduces a light-front Hamiltonian formalism for gauge theories, offering new nonperturbative methods for QCD and electroweak spectrum calculations, including a novel gauge quantization approach and implications for particle interactions.

Contribution

It presents a new method for quantizing gauge theories in light-cone gauge using Dirac brackets, ensuring unitarity and renormalizability in massive gauge theories.

Findings

A unitary, renormalizable light-front electroweak theory with spontaneous symmetry breaking.

Development of an event amplitude generator for computing renormalized amplitudes.

Emphasis on the role of final-state interactions in high-energy scattering processes.

Abstract

Light-front wavefunctions provide a frame-independent representation of hadrons in terms of their physical quark and gluon degrees of freedom. The light-front Hamiltonian formalism provides new nonperturbative methods for obtaining the QCD spectrum and eigensolutions, including resolvant methods, variational techniques, and discretized light-front quantization. A new method for quantizing gauge theories in light-cone gauge using Dirac brackets to implement constraints is presented. In the case of the electroweak theory, this method of light-front quantization leads to a unitary and renormalizable theory of massive gauge particles, automatically incorporating the Lorentz and 't Hooft conditions as well as the Goldstone boson equivalence theorem. Spontaneous symmetry breaking is represented by the appearance of zero modes of the Higgs field leaving the light-front vacuum equal to the perturbative vacuum. I also discuss an "event amplitude generator" for automatically computing renormalized amplitudes in perturbation theory. The importance of final-state interactions for the interpretation of diffraction, shadowing, and single-spin asymmetries in inclusive reactions such as deep inelastic lepton-hadron scattering is emphasized