The BPS spectra of gauge theories in two and four dimensions

Abstract

We study N = (2, 2) supersymmetric abelian gauge theories in two dimensions. The exact BPS spectrum of these models is shown to coincide with the spectrum of massive hypermultiplets of certain N = 2 supersymmetric gauge theories in four dimensions. A special case of these results involves a surprising connection between four-dimensional N = 2 SQCD with N colours and Nf ^gt; N flavours at the root of the baryonic Higgs branch and the supersymmetric CP2N-Nf-1 σ-model in two dimensions. This correspondence implies a new prediction for the strong-coupling spectrum of the four-dimensional theory.