Nonlinear sigma model approach for chiral fluctuations and symmetry breakdown in the Nambu–Jona-Lasinio model

2000/06/09 by Egor Babaev
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics #cond-mat #hep-ph #hep-th

paper · pdf · doi:10.1103/physrevd.62.074020

published as Phys.Rev. D62 (2000) 074020 · accepted to Phys. Rev. D. Latest updates of this and related papers are available at http://www.teorfys.uu.se/PEOPLE/egor/

arxiv created 2000/06/09 · openalex publication_date 2000/09/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

This paper is organized in two parts. We start with the observation that the recent claim that the chiral symmetry in the Nambu--Jona-Lasinio (NJL) model is necessarily restored by violent chiral fluctuations at N_c=3 [H. Kleinert and B. Van den Bossche, Phys. Lett. B 474, 336 (2000)] appears to be incorrect since the critical stiffness of the effective nonlinear sigma model used in the above reference is not a universal quantity in 3+1 dimensions. In the second part we discuss a modified NJL model, where the critical stiffness is expressed via an additional cutoff parameter. This model displays a symmetry breakdown, and also under certain conditions the chiral fluctuations give rise to a phase analogous to pseudogap phase of superconductors with strong coupling or low carrier density.

Citations

• Dynamical Model of Elementary Particles Based on an Analogy with Superconductivity. I
• Ordering, metastability and phase transitions in two-dimensional systems
• Criterion for Dominance of Directional over Size Fluctuations in Destroying Order
• Dynamical Model of Elementary Particles Based on an Analogy with Superconductivity. II