U(1)xSU(m)_1 Theory and c=m W_{1+\infty} Minimal Models in the Hierarchical Quantum Hall Effect

Abstract

Two classes of Conformal Field Theories have been proposed to describe the Hierarchical Quantum Hall Effect:the multi-component bosonic theory, characterized by the symmetry U(1)xSU(m)_1 and the W_{1+\infty} minimal models with central charge c=m. In spite of having the same spectrum of edge excitations, they manifest differences in the degeneracy of the states and in the quantum statistics, which call for a more detailed comparison between them. Here, we describe their detailed relation for the general case, c=m and extend the methods previously published for c < 4. Specifically, we obtain the reduction in the number of degrees of freedom from the multi-component Abelian theory to the minimal models by decomposing the characters of the U(1)xSU(m)_1 representations into those of the c=m W_{1+\infty} minimal models. Furthermore, we find the Hamiltonian whose renormalization group flow interpolates between the two models, having the W_{1+\infty} minimal models as infra-red fixed point.