We develop a systematic method to solve the Cardy condition for the coset
conformal field theory G/H. The problem is equivalent to finding a non-negative
integer valued matrix representation (NIM-rep) of the fusion algebra. Based on
the relation of the G/H theory with the tensor product theory G x H, we give a
map from NIM-reps of G x H to those of G/H. Our map provides a large class of
NIM-reps in coset theories. In particular, we give some examples of NIM-reps
not factorizable into the G and the H sectors. The action of the simple
currents on NIM-reps plays an essential role in our construction. As an
illustration of our procedure, we consider the diagonal coset SU(2)_5 x SU(2)_3
/SU(2)_8 to obtain a new NIM-rep based on the conformal embedding su(2)_3
\oplus su(2)_8 \subset sp(6)_1.Comment: 43 pages, 6 figures; (v2) arguments about the actions of simple
currents on NIM-reps modified. references added; (v3) misplaced figure
correcte
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.