Combinatorial aspects of boundary loop models

Jesper Lykke Jacobsen (1, 2) , Hubert Saleur (2, 3)

1 LPTMS - Laboratoire de Physique Théorique et Modèles Statistiques
2 SPhT - Service de Physique Théorique
3 Department of Physics and Astronomy [USC, Los Angeles]

We discuss in this paper combinatorial aspects of boundary loop models, that is models of self-avoiding loops on a strip where loops get different weights depending on whether they touch the left, the right, both or no boundary. These models are described algebraically by a generalization of the Temperley-Lieb algebra, dubbed the two-boundary TL algebra. We give results for the dimensions of TL representations and the corresponding degeneracies in the partition functions. We interpret these results in terms of fusion and in the light of the recently uncovered A_n large symmetry present in loop models, paving the way for the analysis of the conformal field theory properties. Finally, we propose conjectures for determinants of Gram matrices in all cases, including the two-boundary one, which has recently been discussed by de Gier and Nichols.

Mots clés: two-boundary Temperley-Lieb algebra; representation theory; eigenvalue amplitude; boundary loop model; Gram matrix

Domaines: Physique mathématique [math-ph]; Physique mathématique [math-ph]; Mécanique statistique [cond-mat.stat-mech]; Théorie des représentations [math.RT]

Jesper Lykke Jacobsen, Hubert Saleur. Combinatorial aspects of boundary loop models. 2008. ⟨hal-00170099v2⟩