Operator-algebraic construction of the deformed Sine-Gordon model

Abstract: We consider the construction of integrable quantum field theories in the operator-algebraic approach, which is based on quantum fields localized in infinitely extended wedge regions. This approach has been successful for the construction of a class of models with scalar $S$-matrices and without bound states. In extension of these results, we apply similar methods to $S$-matrices with poles in the physical strip (bound states''). Specifically, we consider a deformed version of the Sine-Gordon model, containing only breathers. We exhibit wedge-local fields in this model, which differ from those in non-bound state models by an additive term, the so calledbound state operator''.