{ "id": "1101.3872", "version": "v1", "published": "2011-01-20T11:40:51.000Z", "updated": "2011-01-20T11:40:51.000Z", "title": "Monomorphism categories, cotilting theory, and Gorenstein-projective modules", "authors": [ "Pu Zhang" ], "comment": "20 pages", "categories": [ "math.RT" ], "abstract": "The monomorphism category $\\mathcal S_n(\\mathcal X)$ is introduced, where $\\mathcal X$ is a full subcategory of the module category $A$-mod of Artin algebra $A$. The key result is a reciprocity of the monomorphism operator $\\mathcal S_n$ and the left perpendicular operator $^\\perp$: for a cotilting $A$-module $T$, there is a canonical construction of a cotilting $T_n(A)$-module ${\\rm \\bf m}(T)$, such that $\\mathcal S_n(^\\perp T) = \\ ^\\perp {\\rm \\bf m}(T)$. As applications, $\\mathcal S_n(\\mathcal X)$ is a resolving contravariantly finite subcategory in $T_n(A)$-mod with $\\hat{\\mathcal S_n(\\mathcal X)} = T_n(A)$-mod if and only if $\\mathcal X$ is a resolving contravariantly finite subcategory in $A$-mod with $\\hat{\\mathcal X} = A$-mod. For a Gorenstein algebra $A$, the category $T_n(A)\\mbox{-}\\mathcal Gproj$ of Gorenstein-projective $T_n(A)$-modules can be explicitly determined as $\\mathcal S_n(^\\perp A)$. Also, self-injective algebras $A$ can be characterized by the property $T_n(A)\\mbox{-}\\mathcal Gproj = \\mathcal S_n(A)$. Using $\\mathcal S_n(A)= \\ ^\\perp {\\rm \\bf m}(D(A_A))$, a characterization of $\\mathcal S_n(A)$ of finite type is obtained.", "revisions": [ { "version": "v1", "updated": "2011-01-20T11:40:51.000Z" } ], "analyses": { "subjects": [ "16G10", "16E65", "16G50" ], "keywords": [ "monomorphism category", "gorenstein-projective modules", "cotilting theory", "resolving contravariantly finite subcategory", "left perpendicular operator" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable" } } }