arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2205.03097math.CTmath.RT
收藏

扩张范畴与n-外角函子的刻画

The category of extensions and a characterisation of $n$-exangulated functors

Raphael Bennett-Tennenhaus, Johanne Haugland, Mads Hustad Sandøy, Amit Shah

AI总结:

本文通过扩张范畴研究n-外角范畴,刻画了n-外角函子与自然变换,并在小n-外角范畴与小正合范畴的2-范畴之间建立了2-函子,同时构造了多种实例。

摘要:

加性范畴在数学及相关学科中发挥着基础性作用。给定一个配备双加性函子的加性范畴,可以构造其扩张范畴,该范畴编码了重要的结构信息。我们研究扩张范畴之间的函子如何与原范畴层面上的函子相关联。当所讨论的加性范畴是n-外角范畴时,这将导出n-外角函子的刻画。我们的方法使我们能够从2-范畴的视角研究n-外角范畴。我们引入n-外角自然变换,并利用扩张范畴对其加以刻画。我们的刻画使我们能够在小的n-外角范畴与小的正合范畴的2-范畴之间建立一个2-函子。我们还证明了一个不假设小性的类似结果。我们运用我们的理论来构造n-外角函子和自然变换的各种例子。尽管本文的动机源于表示论和n-外角范畴的研究,但我们的结果具有广泛的适用性:其中一些结果只需要一个配备双加性函子的加性范畴,无需任何额外假设;另一些结果则可以通过赋予加性范畴其分裂n-外角结构来应用。

英文摘要:

Additive categories play a fundamental role in mathematics and related disciplines. Given an additive category equipped with a biadditive functor, one can construct its category of extensions, which encodes important structural information. We study how functors between categories of extensions relate to those at the level of the original categories. When the additive categories in question are $n$-exangulated, this leads to a characterisation of $n$-exangulated functors. Our approach enables us to study $n$-exangulated categories from a $2$-categorical perspective. We introduce $n$-exangulated natural transformations and characterise them using categories of extensions. Our characterisations allow us to establish a $2$-functor between the $2$-categories of small $n$-exangulated categories and small exact categories. A similar result with no smallness assumption is also proved. We employ our theory to produce various examples of $n$-exangulated functors and natural transformations. Although the motivation for this article stems from representation theory and the study of $n$-exangulated categories, our results are widely applicable: several require only an additive category equipped with a biadditive functor with no extra assumptions; others can be applied by endowing an additive category with its split $n$-exangulated structure.

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。

↑