Dispersion Relations in Gauge Theories with Confinement
Abstract
Description
The analytic structure of {\it physical} amplitudes is considered for gauge theories with confinement of excitations corresponding to the elementary fields. Confinement is defined in terms of the BRST algebra. BRST-invariant, local, composite fields are introduced, which interpolate between physical asymptotic states. It is shown that the singularities of physical amplitudes are the same as in an effective theory with only physical fields. In particular, there are no structure singularities (anomalous thresholds) associated with confined constituents, like quarks and gluons. The old proofs of dispersion relations for hadronic amplitudes remain valid in QCD.
Plenary talk presented at the XVIIIth International Workshop on High Energy Physics and Field Theory, Moscow-Protvino, June 1995. To be published in the Proceedings. 13 pages, Latex
Plenary talk presented at the XVIIIth International Workshop on High Energy Physics and Field Theory, Moscow-Protvino, June 1995. To be published in the Proceedings. 13 pages, Latex