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arXiv · hep-lat/9701015

Series Expansions for the Massive Schwinger Model in Hamiltonian lattice theory

C. J. Hamer·Zheng Weihong·J. Oitmaa
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Abstract

It is shown that detailed and accurate information about the mass spectrum of the massive Schwinger model can be obtained using the technique of strong-coupling series expansions. Extended strong-coupling series for the energy eigenvalues are calculated, and extrapolated to the continuum limit by means of integrated differential approximants, which are matched onto a weak-coupling expansion. The numerical estimates are compared with exact results, and with finite-lattice results calculated for an equivalent lattice spin model with long-range interactions. Both the heavy fermion and the light fermion limits of the model are explored in some detail.

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C. J. Hamer, Zheng Weihong, J. Oitmaa. 1997-02-04. Series Expansions for the Massive Schwinger Model in Hamiltonian lattice theory. https://doi.org/10.1103/physrevd.56.55

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