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Sine-Gordon Expectation Values of Exponential Fields With Variational Perturbation Theory

Wen-Fa Lu
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Abstract

In this paper, expectation values of exponential fields in the 2-dimensional Euclidean sine-Gordon field theory are calculated with variational perturbation approach up to the second order. Our numerical analysis indicates that for not large values of the exponential-field parameter $a$, our results agree very well with the exact formula conjectured by Lukyanov and Zamolodchikov in Nucl. Phys. B 493, 571 (1997).

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Wen-Fa Lu. 2004-10-09. Sine-Gordon Expectation Values of Exponential Fields With Variational Perturbation Theory. https://doi.org/10.1016/j.physletb.2004.10.001

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