English

Discussing the U(1)-Problem of QED_2 without Instantons

High Energy Physics - Theory 2009-10-30 v1

Abstract

We construct QED_2 with mass and flavor and an extra Thirring term. The vacuum expectation values are carefully decomposed into clustering states using the U(1)-axial symmetry of the considered operators and a limiting procedure. The properties of the emerging expectation functional are compared to the proposed theta-vacuum of QCD. The massive theory is bosonized to a generalized Sine-Gordon model (GSG). The structure of the vacuum of QED_2 manifests itself in symmetry properties of the GSG. We study the U(1)-problem and derive a Witten-Veneziano-type formula for the masses of the pseudoscalars determined from a semiclassical approximation.

Keywords

Cite

@article{arxiv.hep-th/9602027,
  title  = {Discussing the U(1)-Problem of QED_2 without Instantons},
  author = {Christof Gattringer},
  journal= {arXiv preprint arXiv:hep-th/9602027},
  year   = {2009}
}

Comments

Accepted for publication in Annals of Physics