Description
We define defects in critical lattice models that give rise to conformal field theory topological defects in the continuum limit. We focus on models based on the Temperley-Lieb algebra, with applications to non-unitary models such as percolation or self-avoiding walks. Our approach is algebraic and focusses on the defects from two points of view: the "crossed channel" where the defect is seen as an operator acting on the Hilbert space of the models, and the "direct channel" where it corresponds to a modification of the basic Hamiltonian with an impurity. Algebraic characterizations and constructions are proposed in both points of view.
