Confinement and Green functions in Landau-gauge QCD
arXiv:0812.2896
Abstract
In a functional approach to QCD the infrared behaviour of Landau gauge Green functions is investigated. Positivity violation for, and thus confinement of, gluons is demonstrated, and the analytic structure of the gluon propagator is studied. Quark confinement is related to an infrared divergence of the quark-gluon vertex. In the latter various components are dynamically induced due to the spontaneous breaking of chiral symmetry. As a result an infrared finite running coupling in the Yang-Mills sector is derived whereas the running coupling related to the quark-gluon vertex is infrared divergent. Based on a truncation for the quark-gluon vertex Dyson-Schwinger equation, which respects the analytically determined infrared behavior, numerical results for the coupled system of the quark propagator and vertex Dyson-Schwinger equations are presented. The resulting quark mass function as well as the vertex function show only a very weak dependence on the current quark mass in the deep infrared. From this we infer by an analysis of the quark-quark scattering kernel a linearly rising quark potential with an almost mass independent string tension in the case of broken chiral symmetry.
10 pages. 9 figures; invited plenary talk given at the 8th Conference Quark Confinement and the Hadron Spectrum, September 1-6, 2008, Mainz, Germany
References in corpus (22)
- Wilson loops in large N field theories
- The Infrared Behavior of QCD Green's Functions - Confinement, Dynamical Symmetry Breaking, and Hadrons as Relativistic Bound States
- Infrared Properties of QCD from Dyson-Schwinger equations
- The Infrared Behavior of Gluon and Ghost Propagators in Landau Gauge QCD
- On the Infrared Exponent for Gluon and Ghost Propagation in Landau Gauge QCD
- A Solution to Coupled Dyson-Schwinger Equations for Gluons and Ghosts in Landau Gauge
- Non-perturbative Propagators, Running Coupling and Dynamical Quark Mass of Landau gauge QCD
- Infrared Exponents and Running Coupling of SU(N) Yang-Mills Theories
- Scaling behavior and positivity violation of the gluon propagator in full QCD
- The Elusiveness of Infrared Critical Exponents in Landau Gauge Yang--Mills Theories
- Uniqueness of infrared asymptotics in Landau gauge Yang-Mills theory II
- Numerical Study of the Ghost-Gluon Vertex in Landau gauge
- Infrared singularities in Landau gauge Yang-Mills theory
- Verifying the Kugo-Ojima Confinement Criterion in Landau Gauge Yang-Mills Theory
- Algorithmic derivation of Dyson-Schwinger Equations
- U_A(1) anomaly and eta' mass from an infrared singular quark-gluon vertex
- Relativistic corrections to the static potential at O(1/m) and O(1/m^2)
- What the Infrared Behavior of QCD Green Functions can tell us about Confinement in the Covariant Gauge
- Mass production requires precision engineering
- QCD Green Functions and their Application to Hadron Physics
- Aspects of the confinement mechanism in Landau gauge QCD
- Lower dimensional Yang-Mills theory as a laboratory to study the infrared regime