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arXiv · hep-th/9312102

Functional Integral Approach to the N-Flavor Schwinger Model

Christof Gattringer·Erhard Seiler
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Abstract

We study massless QED_2 with N flavors using path integrals. We identify the sector that is generated by the N^2 classically conserved vector currents. One of them (the U(1) current) creates a massive particle, while the others create massless ones. We show that the mass spectrum obeys a Witten-Veneziano type formula. Two theorems on n-point functions clarify the structure of the Hilbert space. Evaluation of the Fredenhagen-Marcu order parameter indicates that a confining force exists only between charges that are integer multiples of +/- Ne, whereas charges that are nonzero mod(N) screen their confining forces and lead to non-vacuum sectors. Finally we identify operators that violate clustering, and decompose the theory into clustering theta vacua.

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Christof Gattringer, Erhard Seiler. 1993-12-13. Functional Integral Approach to the N-Flavor Schwinger Model. https://doi.org/10.1006/aphy.1994.1062

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