The exact equivalence of the one-flavour lattice Thirring model with Wilson fermions to a two-colour loop model

Within Euclidean lattice field theory an exact equivalence between the one-flavour 2D Thirring model with Wilson fermions and Wilson parameter r = 1 to a two-colour loop model on the square lattice is established. For noninteracting fermions this model reduces to an exactly solved loop model which is known to be a free fermion model. The two-colour loop model equivalent to the Thirring model can also be understood as a 4-state 49-vertex model. E-mail: [email protected] Present address