After giving a short description, in terms of action of categories, of some of the structures associated with sl(2) and sl(3) boundary conformal field theories on a torus, we provide tables of dimensions describing the semisimple and co-semisimple blocks of the corresponding weak bialgebras (quantum groupoids), tables of quantum dimensions and orders, and tables describing induction -restriction. For reasons of size, the sl(3) tables of induction are only given for theories with self-fusion (existence of a monoidal structure).II, et du Sud Toulon-Var, affiliéà la FRUMAM (FR 2291). ‡ Email: schieber@cbpf.br § CBPF -Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro.
The stageIn this paper A k is the fusion category of the affine algebra sl(2), or sl (3), at level k, or equivalently, the category of representations with non-zero q-dimension for the quantum groups SL(2) q or SL(3) q at roots of unity (set q = exp(iπ/κ), with κ = k + 2 for sl(2) and κ = k + 3 for sl (3)). This category is additive (existence of ⊕), monoidal (existence of ⊗ : A k × A k → A k , with associativity constraints, unit object, etc.), tensorial (⊗ is a bifunctor), complex-linear, rigid (existence of duals), finite (finitely many irreducible objects), and semisimple, with irreducible unit object. It is also modular (braided, with invertible S-matrix) and ribbon (in particular balanced -or tortile). We refer to the literature [29], [27], [1] for a detailed description of these structures. The Grothendieck ring of this monoidal category comes with a special basis (corresponding to simple objects), it is usually called the fusion ring, or the Verlinde algebra. The corresponding structure constants, encoded by the so -called fusion matrices (N n ) p q , are therefore non -negative integers: NIM-reps in CFT terminology. The rigidity property of the category implies that (N n ) pq = (N n ) qp , where n refers to the dual object i.e., in our case, to the conjugate representation, so that the fusion ring is automatically a based Z + ring in the sense of [39] (maybe it would be better to call it "rigid"). In the case of sl (2), this is a ring with one generator (corresponding to the fundamental representation), and fusion matrices are symmetric, because n = n. In the case of sl (3), it is convenient to use two generators that are conjugate to one another; they correspond to the two fundamental representations. Multiplication by the chosen generator is encoded by a particular fusion matrix N 1 ; it is a finite size matrix of dimension r × r, with r = k + 1 for sl(2) and r = k(k + 1)/2 for sl(3). Since its elements are non negative integers, it can be interpreted as the adjacency matrix of a graph, which is the Cayley graph of multiplication by this generator, that we call the McKay graph of the category. Edges are non oriented in the case of sl(2) (rather, they carry both orientations) and are oriented in the case of sl(3). Irreducible representations are denoted by λ p , with p ≥ 0, in the first case, and λ pq , with p, q ≥ 0 in the next. Notice t...