What the infrared behavior of qcd vertex functions in Landau gauge can tell us about confinement


Alkofer R., Fischer C. S. , Llanes-Estrada F. J. , Schwenzer K. O.

INTERNATIONAL JOURNAL OF MODERN PHYSICS E, cilt.16, sa.9, ss.2720-2732, 2007 (SCI İndekslerine Giren Dergi) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 16 Konu: 9
  • Basım Tarihi: 2007
  • Doi Numarası: 10.1142/s0218301307008367
  • Dergi Adı: INTERNATIONAL JOURNAL OF MODERN PHYSICS E
  • Sayfa Sayıları: ss.2720-2732

Özet

The infrared behavior of Landau gauge QCD vertex functions is investigated employing a skeleton expansion of the Dyson-Schwinger and Renormalization Group equations. Results for the ghost-gluon, three-gluon, four-gluon and quark-gluon vertex functions are presented. Positivity violation of the gluon propagator, and thus gluon confinement, is demonstrated. Results of the Dyson-Schwinger equations for a finite volume are compared to corresponding lattice data. It is analytically demonstrated that a linear rising potential between heavy quarks can be generated by infrared singularities in the dressed quark-gluon vertex. The selfconsistent mechanism that generates these singularities necessarily entails the scalar Dirac amplitudes of the full vertex and the quark propagator. These can only be present when chiral symmetry is broken, either explicitly or dynamically.