The scaling limit of the spectrum, S matrix, and of the form factors of the
polarization operator in the six vertex model has been found. The result for
the form factors is consistent with the form factors of the sine-Gordon model
found recently by Lukyanov. We discuss the origin of the structure of the free
field representation for the sine-Gordon model at the critical coupling from
the point of view of the lattice model.Comment: 14 pages, no figures, plain TeX, all macros included, minor misprints
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