The Ising quantum chain with n arbitrarily placed defects is solved exactly. At the bulk critical point, the model is conformally invariant if and only if the defects form a commensurate structure. The central charge is obtained and is found to be a discontinuous function of the distances of the defects, while the critical exponents (generalized corner exponents) depend continuously on the positions of the defects. It is argued that the discontinuous behavior of the central charge is a general feature not restricted to the Ising model.
ASJC Scopus subject areas
- Nuclear and High Energy Physics