Almost split sequences for non-regular modules
نویسندگان
چکیده
منابع مشابه
On F -Almost Split Sequences
Let Λ be an Artinian algebra and F an additive subbifunctor of ExtΛ(−,−) having enough projectives and injectives. We prove that the dualizing subvarieties of mod Λ closed under F -extensions have F -almost split sequences. Let T be an F -cotilting module in mod Λ and S a cotilting module over Γ = End(T ). Then Hom(−, T ) induces a duality between F -almost split sequences in ⊥F T and almost sp...
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We show that almost split sequences in the category of comodules over a coalgebra Γ with finite-dimensional right-hand term are direct limits of almost split sequences over finite dimensional subcoalgebras. In previous work we showed that such almost split sequences exist if the right hand term has a quasifinitely copresented linear dual. Conversely, taking limits of almost split sequences over...
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 1993
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm-143-2-183-190