Logarithmic tensor category theory for generalized modules for a conformal vertex algebra, I: Introduction and strongly graded algebras and their generalized modules
Yi-Zhi Huang, James Lepowsky, Lin Zhang
备注：
Part I of a series of 8 papers generalizing the results in and collectively replacing arXiv:0710.2687 (which in turn replaced arXiv:math/0609833 for technical reasons), with new titles. 82 pages. Trivial changes, including theorem numbers. Additional acknowledgments. References added. Versions 7, 6 and 5 are identical, except for problems encountered in the replacement procedure
This is the first 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. This theory generalizes the tensor category theory for modules for a vertex operator algebra previously developed in a series of papers by the first two authors to suitable module categories for a "conformal vertex algebra" or even more generally, for a "Möbius vertex algebra." We do not require the module categories to be semisimple, and we accommodate modules with generalized weight spaces. As in the earlier series of papers, our tensor product functors depend on a complex variable, but in the present generality, the logarithm of the complex variable is required; the general representation theory of vertex operator algebras requires logarithmic structure. This work includes the complete proofs in the present generality and can be read independently of the earlier series of papers. Since this is a new theory, we present it in detail, including the necessary new foundational material. In addition, with a view toward anticipated applications, we develop and present the various stages of the theory in the natural, general settings in which the proofs hold, settings that are sometimes more general than what we need for the main conclusions. In this paper (Part I), we give a detailed overview of our theory, state our main results and introduce the basic objects that we shall study in this work. We include a brief discussion of some of the recent applications of this theory, and also a discussion of some recent literature.
Trivializing group actions on braided crossed tensor categories and graded braided tensor categories
对于交换群$ A $，研究了交叉辫状$ A $ -范畴与$ A $ -作用和$ A $ -分次辫状张量范畴的平凡化之间的紧密联系.此外，我们证明了一个阻碍的存在平凡化的一个范畴的群作用$T$的monoidal范畴$\mathcal{C}$是由一个元素$O(T)\in H^2(G,\operatorname{Aut}_\otimes(\operatorname{Id}_{\mathcal{C}}))$。在$O(T)=0$的情况下，障碍物的集合形成$\operatorname{Hom}(G,\operatorname{Aut}_\otimes(\operatorname{Id}_{\mathcal{C}}))$上的torsor，其中$\operatorname{Aut}_\otimes(\operatorname{Id}_{\mathcal{C}})$是恒等式的张量自然自同构的阿贝尔群。平凡化的上同调解释，以及arXiv：0909.3140中发展的（忠实分级）辫状$A$ -交叉张量范畴的同伦分类，使我们能够提供一种构造忠实$A$ -分级辫状张量范畴的方法.我们举两个例子。首先，我们计算了与点半单张量范畴相关联的辫状交叉范畴平凡化存在的障碍。在第二个例子中，我们计算显式公式的编织$\mathbb{Z}/2$交叉结构的Tambara-Yamagami融合类别，因此，在arXiv：数学/00…
