English

Screening vs. Confinement in 1+1 Dimensions

High Energy Physics - Theory 2009-10-28 v2 High Energy Physics - Phenomenology

Abstract

We show that, in 1+1 dimensional gauge theories, a heavy probe charge is screened by dynamical massless fermions both in the case when the source and the dynamical fermions belong to the same representation of the gauge group and, unexpectedly, in the case when the representation of the probe charge is smaller than the representation of the massless fermions. Thus, a fractionally charged heavy probe is screened by dynamical fermions of integer charge in the massless Schwinger model, and a colored probe in the fundamental representation is screened in QCD2QCD_2 with adjoint massless Majorana fermions. The screening disappears and confinement is restored as soon as the dynamical fermions are given a non-zero mass. For small masses, the string tension is given by the product of the light fermion mass and the fermion condensate with a known numerical coefficient. Parallels with 3+1 dimensional QCDQCD and supersymmetric gauge theories are discussed.

Keywords

Cite

@article{arxiv.hep-th/9511104,
  title  = {Screening vs. Confinement in 1+1 Dimensions},
  author = {D. J. Gross and I. R. Klebanov and A. V. Matytsin and A. V. Smilga},
  journal= {arXiv preprint arXiv:hep-th/9511104},
  year   = {2009}
}

Comments

29 pages, latex, no figures. slight change in the wording on page 2, references added