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Finite-Volume Form Factors in Semiclassical Approximation

G. Mussardo·V. Riva·G. Sotkov
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Abstract

A semiclassical approach is used to obtain Lorentz covariant expressions for the form factors between the kink states of a quantum field theory with degenerate vacua. Implemented on a cylinder geometry it provides an estimate of the spectral representation of correlation functions in a finite volume. Illustrative examples of the applicability of the method are provided by the Sine-Gordon and the broken ϕ^4 theories in 1+1 dimensions.

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G. Mussardo, V. Riva, G. Sotkov. 2003-07-14. Finite-Volume Form Factors in Semiclassical Approximation. https://doi.org/10.1016/j.nuclphysb.2003.08.017

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