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Free field construction for the eight-vertex model: representation for form factors

Michael Lashkevich
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Abstract

The free field realization of the eight-vertex model is extended to form factors. It is achieved by constructing off-diagonal with respect to the ground state sectors matrix elements of the $Λ$ operator which establishes a relation between corner transfer matrices of the eight-vertex model and of the SOS model. As an example, the two-particle form factor of the $σ^z$ operator is evaluated explicitly.

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Michael Lashkevich. 2001-12-06. Free field construction for the eight-vertex model: representation for form factors. https://doi.org/10.1016/s0550-3213(01)00598-3

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