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arXiv · 1501.05185

Triangular objects and systematic K-theory

Thomas Huettemann·Zuhong Zhang
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Abstract

We investigate modules over "systematic" rings. Such rings are "almost graded" and have appeared under various names in the literature; they are special cases of the G-systems of Grzeszczuk. We analyse their K-theory in the presence of conditions on the support, and explain how this generalises and unifies calculations of graded and filtered K-theory scattered in the literature. Our treatment makes systematic use of the formalism of idempotent completion and a theory of triangular objects in additive categories, leading to elementary and transparent proofs throughout.

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Thomas Huettemann, Zuhong Zhang. 2015-01-21. Triangular objects and systematic K-theory. https://doi.org/10.1080/00927872.2016.1226870

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