Harder-Narasimhan categories
نویسنده
چکیده
We propose a generalization of Quillen’s exact category — arithmetic exact category and we discuss conditions on such categories under which one can establish the notion of Harder-Narasimhan filtrations and Harder-Narsimhan polygons. Furthermore, we show the functoriality of Harder-Narasimhan filtrations (indexed by R), which can not be stated in the classical setting of Harder and Narasimhan’s formalism.
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