arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1507.01460math.CTmath.AT
收藏

Kan扩张与$\infty$ -范畴的模演算

Kan extensions and the calculus of modules for $\infty$-categories

Emily Riehl, Dominic Verity

摘要:

$(\infty,1)$ -范畴的各种模型,包括拟范畴、完备Segal空间、Segal范畴和自然标记单纯集,都可以看作是$\infty$ -宇宙的对象。在一般的$\infty$ -宇宙中,我们称其对象为$\infty$ -范畴,我们在$\infty$ -范畴之间引入模(也称为原函子或对应),具体表现为具有群胚纤维的适当定义的纤维化的跨度。顾名思义,从$A$到$B$的模块在适当的意义上是配备有$A$的左动作和$B$的右动作的$\infty$类别。应用米田引理的纤维化形式,我们开发了一个通用演算的模块,证明他们自然组装成一个多范畴的结构称为虚拟设备,这是已知的是一个强大的设置,在其中开发正式的范畴论。使用微积分的模块,它是简单的定义和研究逐点Kan扩展,我们涉及的情况下,carnival封闭的$\infty$ -cosmoi,限制和colimits的图值在一个$\infty$类,如在以前的工作中介绍。

英文摘要:

Various models of $(\infty,1)$-categories, including quasi-categories, complete Segal spaces, Segal categories, and naturally marked simplicial sets can be considered as the objects of an $\infty$-cosmos. In a generic $\infty$-cosmos, whose objects we call $\infty$-categories, we introduce modules (also called profunctors or correspondences) between $\infty$-categories, incarnated as as spans of suitably-defined fibrations with groupoidal fibers. As the name suggests, a module from $A$ to $B$ is an $\infty$-category equipped with a left action of $A$ and a right action of $B$, in a suitable sense. Applying the fibrational form of the Yoneda lemma, we develop a general calculus of modules, proving that they naturally assemble into a multicategory-like structure called a virtual equipment, which is known to be a robust setting in which to develop formal category theory. Using the calculus of modules, it is straightforward to define and study pointwise Kan extensions, which we relate, in the case of cartesian closed $\infty$-cosmoi, to limits and colimits of diagrams valued in an $\infty$-category, as introduced in previous work.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑