Violation of S-matrix factorization in the massive Thirring model - art. no. 125019

We present a counterexample which shows the violation of the S-matrix facto rization in the massive Thirring model. This is done by solving the PBC equ ations of the massive Thirring model exactly but numerically. The violation of the S-matrix factorization is related to the fact that the crossing sym metry and the factorization do not commute with each other. This confirms t hat the soliton-antisoliton S-matrix factorization picture of the sine-Gord on model is semiclassical and does not lead to a full quantization procedur e of the massive Thirring model. [S0556-2821(98)06122-0].