We consider the lattice models based on affine algebras described by Jimbo et al., for the algebras 𝐴𝐵𝐶𝐷 and by Kuniba et al. for 𝐺2. We find a general formula for the crossing multipliers of these models, with the result that these crossing multipliers are given by the principally specialized characters of the model in question. Therefore we conjecture that the crossing multipliers in a large class of solvable interaction round the face lattice models are given by the characters of the conformal field theory on which they are based. We also elaborate on some details of the computation of the Local state probability of these models, conjecturing an expression for it.
Abstract We study the large class of solvable lattice models, based on the data of conformal field theory. These models are constructed from any conformal field theory. We consider the lattice models based on affine algebras described by Jimbo et al, for the algebras ABCD and by Kuniba et al for G 2. We find a general formula for the crossing multipliers of these models. It is shown that these crossing multipliers are also given by the principally specialized characters of the model in question. Therefore we conjecture that the crossing multipliers in this large class of solvable interaction round the face lattice models are given by the characters of the conformal field theory on which they are based. We use this result to study the local state probabilities of these models and show that they are given by the branching rule, in regime III.
We conjecture the inversion relations for thermalized solvable interaction round the face (IRF) two dimensional lattice models. We base ourselves on an ansatz for the Baxterization described in the 90's. We solve these inversion relations in the four main regimes of the models, to give the free energy of the models, in these regimes. We use the method of Baxter in the calculation of the free energy of the hard hexagon model. We believe these results to be quite general, shared by most of the known IRF models. Our results apply equally well to solvable vertex models. Using the expression for the free energy we calculate the critical exponent α, and from it the dimension of the perturbing (thermal) operator in the fixed point conformal field theory (CFT). We show that it matches either the coset O/G or G/O, where O is the original CFT used to define the model and G is some unknown CFT, depending on the regime. This agrees with known examples of such models by Huse and Jimbo et al.
A family of interacting bosonic models is studied. A picture is suggested where each such conformal field theory is tensored with a conjugate one to give a free bosonic theory. It is shown that the lattice of the bosonic theory is determined in each case, and how the spectrum and correlation functions can be calculated. It is explained how flat directions can arise in such theories, allowing for an exact solution for a family of parameters. A large class of examples is discussed in detail. It is shown that for any rational value of the central charge c ≥ 3 there is an infinite number of distinct rational N = 2 theories which can be contracted by this method.
The multiscale entanglement renormalization ansatz (MERA) can be used, in its scale invariant version, to describe the ground state of a lattice system at a quantum-critical point. From the scale invariant MERA one can determine the local scaling operators of the model. Here we show that, in the presence of a global symmetry
G, it is also possible to determine a class of nonlocal scaling operators. Each operator consists, for a given group element
g∊G, of a semi-infinite string ${\ensuremath{\Gamma}}_{g}^{\ensuremath{\vartriangleleft}}$ with a local operator $\ensuremath{\varphi}$ attached to its open end. In the case of the quantum Ising model,
G=Z2, they correspond to the disorder operator $\ensuremath{\mu}$, the fermionic operators $\ensuremath{\psi}$ and $\overline{\ensuremath{\psi}}$, and all their descendants. Together with the local scaling operators identity
I, spin $\ensuremath{\sigma}$, and energy
ϵ, the fermionic and disorder scaling operators $\ensuremath{\psi}$, $\overline{\ensuremath{\psi}}$, and $\ensuremath{\mu}$ are the complete list of primary fields of the Ising CFT. Therefore the scale invariant MERA allows us to characterize all the conformal towers of this CFT.
Starting from the fusion rules for the algebra SO(5)2 we construct one-dimensional lattice models of interacting anyons with commuting transfer matrices of ‘interactions round the face’ (IRF) type. The conserved topological charges of the anyon chain are recovered from the transfer matrices in the limit of large spectral parameter. The properties of the models in the thermodynamic limit and the low energy excitations are studied using Bethe ansatz methods. Two of the anyon models are critical at zero temperature. From the analysis of the finite size spectrum we find that they are effectively described by rational conformal field theories invariant under extensions of the Virasoro algebra, namely WB2 and WD5, respectively. The latter contains primaries with half and quarter spin. The modular partition function and fusion rules are derived and found to be consistent with the results for the lattice model.