%0 Journal Article %T Lie algebras, Fuchsian differential equations and CFT correlation functions %A Jščrgen Fuchs %A Ingo Runkel %A Christoph Schweigert %J Mathematics %D 2003 %I arXiv %X Affine Kac-Moody algebras give rise to interesting systems of differential equations, so-called Knizhnik-Zamolodchikov equations. The monodromy properties of their solutions can be encoded in the structure of a modular tensor category on (a subcategory of) the representation category of the affine Lie algebra. We discuss the relation between these solutions and physical correlation functions in two-dimensional conformal field theory. In particular we report on a proof for the existence of the latter on world sheets of arbitrary topology. %U http://arxiv.org/abs/hep-th/0301181v1