1110.1929 (Yi-Zhi Huang et al.)

Logarithmic tensor category theory, VII: Convergence and extension
properties and applications to expansion for intertwining maps    [PDF]

Yi-Zhi Huang, James Lepowsky, Lin Zhang

This is the seventh part in a series of papers in which we introduce and develop a natural, general tensor category theory for suitable module categories for a vertex (operator) algebra. In this paper (Part VII), we give sufficient conditions for the existence of the associativity isomorphisms.

View original: http://arxiv.org/abs/1110.1929