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Title: Could Spin-Charge Separation be the Source of Confinement?

Abstract

Yang-Mills gauge field with gauge group SU(2) decomposes into a single charge neutral complex vector, and two spinless charged scalar fields. At high energies these constituents are tightly confined into each other by a compact U(1) interaction, and the Yang-Mills Lagrangian describes the dynamics of asymptotically free massless gauge vectors. But in a low energy and finite density environment the interaction between the constituents can become weak, and a spin-charge separation may occur. We suggest that the separation between the spin and charge with the ensuing condensation of the charged scalars takes place when the Yang-Mills theory enters confinement. The confining phase becomes then surprisingly similar to the superconducting phase of a high-Tc superconductor.

Authors:
 [1];  [2]
  1. Department of Theoretical Physics, Uppsala University P.O. Box 803, S-75108, Uppsala (Sweden)
  2. (France)
Publication Date:
OSTI Identifier:
20787625
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 806; Journal Issue: 1; Conference: International workshop on quantum chromodynamics: Theory and experiment, Conversano, Bari (Italy), 16-20 Jun 2005; Other Information: DOI: 10.1063/1.2163753; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BAG MODEL; BASIC INTERACTIONS; LAGRANGIAN FUNCTION; QUANTUM CHROMODYNAMICS; SCALAR FIELDS; SPIN; SU-2 GROUPS; U-1 GROUPS; VECTORS; YANG-MILLS THEORY

Citation Formats

Niemi, Antti J., and Laboratoire de Mathematiques et Physique Theorique CNRS UMR 6083, Universite de Tours, Parc de Grandmont, F37200, Tours. Could Spin-Charge Separation be the Source of Confinement?. United States: N. p., 2006. Web. doi:10.1063/1.2163753.
Niemi, Antti J., & Laboratoire de Mathematiques et Physique Theorique CNRS UMR 6083, Universite de Tours, Parc de Grandmont, F37200, Tours. Could Spin-Charge Separation be the Source of Confinement?. United States. doi:10.1063/1.2163753.
Niemi, Antti J., and Laboratoire de Mathematiques et Physique Theorique CNRS UMR 6083, Universite de Tours, Parc de Grandmont, F37200, Tours. Thu . "Could Spin-Charge Separation be the Source of Confinement?". United States. doi:10.1063/1.2163753.
@article{osti_20787625,
title = {Could Spin-Charge Separation be the Source of Confinement?},
author = {Niemi, Antti J. and Laboratoire de Mathematiques et Physique Theorique CNRS UMR 6083, Universite de Tours, Parc de Grandmont, F37200, Tours},
abstractNote = {Yang-Mills gauge field with gauge group SU(2) decomposes into a single charge neutral complex vector, and two spinless charged scalar fields. At high energies these constituents are tightly confined into each other by a compact U(1) interaction, and the Yang-Mills Lagrangian describes the dynamics of asymptotically free massless gauge vectors. But in a low energy and finite density environment the interaction between the constituents can become weak, and a spin-charge separation may occur. We suggest that the separation between the spin and charge with the ensuing condensation of the charged scalars takes place when the Yang-Mills theory enters confinement. The confining phase becomes then surprisingly similar to the superconducting phase of a high-Tc superconductor.},
doi = {10.1063/1.2163753},
journal = {AIP Conference Proceedings},
number = 1,
volume = 806,
place = {United States},
year = {Thu Jan 12 00:00:00 EST 2006},
month = {Thu Jan 12 00:00:00 EST 2006}
}
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  • We present an exact diagonalization study of the dynamical spin and density correlation functions in small clusters of the {ital t}-{ital J} model, focusing on the regime of intermediate and low electron densities, {rho}{sub {ital e}}{lt}0.5. In two dimensions (2D) both correlation functions agree remarkably well with the convolution of the single-particle spectral function, i.e., the simplest estimate possible within a Fermi-liquid picture. Deviations from the convolution are shown to originate from symmetry-related selection rules, which are unaccounted for in the convolution estimate. For all fillngs under consideration, we show that the low-energy peaks originate from particle-hole excitations between themore » Fermi momenta, as expected for a Fermi liquid. We contrast this with the behavior in 1D, where spin and density correlation function show the differences characteristic of spin-charge separation and where neither correlation function is approximated well by the convolution.« less
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