[Paper Review] Perturbative QCD with string tension

Ramesh Anishetty|ArXiv.org|Apr 1, 1998

Quantum Chromodynamics and Particle Interactions3 citations

TL;DR

This paper introduces string tension into perturbative QCD without breaking ultraviolet renormalizability, preserving the running coupling while ensuring string tension vanishes at high energies. Using the 1/N expansion, the model achieves analytical tractability with built-in confinement and spontaneous chiral symmetry breaking, demonstrating a consistent framework for non-perturbative QCD features within a perturbative setting.

ABSTRACT

String tension is introduced in perturbative QCD without hindering ultra violet renormalizability . The running gauge coupling constant remains unaltered and the string tension in the high energy limit vanishes asymptotically. Using 1/N techinique the theory can be explicitly analytically computable with cofinement built in . Spontaneous chiral symmetry breakdown along with its Goldstone is exhibited.

Motivation & Objective

• To embed string tension into perturbative QCD without compromising ultraviolet finiteness or renormalizability.
• To maintain the standard running coupling constant of QCD while introducing a dynamically vanishing string tension at high energies.
• To achieve analytical solvability through the 1/N expansion technique, enabling explicit computation of non-perturbative effects.
• To realize confinement and spontaneous chiral symmetry breaking within a perturbative framework.
• To demonstrate that the model supports Goldstone modes associated with chiral symmetry breaking.

Proposed method

• String tension is introduced as a background field in the QCD Lagrangian, preserving gauge invariance and UV renormalizability.
• The 1/N expansion is employed to systematically organize the theory, allowing analytical treatment of non-perturbative phenomena.
• The running coupling remains unaltered, ensuring consistency with standard perturbative QCD at high energies.
• The string tension is shown to vanish asymptotically, consistent with asymptotic freedom.
• Spontaneous chiral symmetry breaking is exhibited through the appearance of massless Goldstone bosons in the large-N limit.
• The model is constructed such that confinement is built in via the string tension, which becomes negligible at high momentum scales.

Experimental results

Research questions

• RQ1 Can string tension be consistently introduced into perturbative QCD without breaking ultraviolet renormalizability?
• RQ2 Does the inclusion of string tension alter the running coupling constant of QCD?
• RQ3 Can the 1/N expansion provide an analytically tractable framework that incorporates both confinement and chiral symmetry breaking?
• RQ4 How does the string tension behave in the high-energy (asymptotic) limit within this model?
• RQ5 Is spontaneous chiral symmetry breaking and its associated Goldstone mode realized in this extended perturbative QCD framework?

Key findings

• String tension is successfully introduced into perturbative QCD without violating ultraviolet renormalizability or altering the running coupling constant.
• The string tension vanishes asymptotically at high energies, preserving asymptotic freedom.
• The 1/N expansion enables explicit analytical computation of the theory, including non-perturbative features like confinement.
• Spontaneous chiral symmetry breaking is realized, with a corresponding massless Goldstone boson emerging in the large-N limit.
• Confinement is built into the model through the string tension, which remains effective at low energies but decouples at high energies.
• The framework provides a consistent perturbative realization of non-perturbative QCD phenomena such as confinement and chiral symmetry breaking.