We introduce a generalization of the Gorenstein injective modules:the Gorenstein FPn-injective modules(denoted by GI_(n)).They are the cycles of the exact complexes of injective modules that remain exact when we apply...We introduce a generalization of the Gorenstein injective modules:the Gorenstein FPn-injective modules(denoted by GI_(n)).They are the cycles of the exact complexes of injective modules that remain exact when we apply a functor Hom(A,-),with A any FP_(n)-injective module.Thus,GL_(o)is the class of classical Gorenstein injective modules,and GI_(1)is the class of Ding injective modules.We prove that over any ring R,for any n≥2,the class GI_(n)is the right half of a perfect cotorsion pair,and therefore it is an enveloping class.For n=1 we show that GI_(1)(i.e.,the Ding injectives)forms the right half of a hereditary cotorsion pair.If moreover the ring R is coherent,then the Ding injective modules form an enveloping class.We also define the dual notion,that of Gorenstein FP_(n)-projectives(denoted by GP_(n)).They generalize the Ding projective modules,and so,the Gorenstein projective modules.We prove that for any n≥2 the class GP_(n)is the left half of a complete hereditary cotorsion pair,and therefore it is special precovering.展开更多
In this paper,we generalize the idea of Song,Zhao and Huang[Czechoslov.Math.J.,70,483±504(2020)]and introduce the notion of right(left)Gorenstein subcategory rg(l,∂)(lg(l,D)),relative to two additive full subcate...In this paper,we generalize the idea of Song,Zhao and Huang[Czechoslov.Math.J.,70,483±504(2020)]and introduce the notion of right(left)Gorenstein subcategory rg(l,∂)(lg(l,D)),relative to two additive full subcategoriesφand∂of an abelian category A.Under the assumption thatφ⊆∂,we prove that the right Gorenstein subcategory rg(l,D)possesses many nice properties that it is closed under extensions,kernels of epimorphisms and direct summands.Whenφ⊆Dandφ⊥D,we show that the right Gorenstein subcategory rg(l,D)admits some kind of stability.Then we discuss a resolution dimension for an object in A,called rg(l,D)-projective dimension.Finally,we prove that if(U,V)is a hereditary cotorsion pair with kernelφhas enough injectives,such that U⊆Dand U⊥∂,then(rg(l,D),φφ)is a weak Auslander±Buchweitz context,whereφis the subcategory of A consisting of objects with finiteφ-projective dimension.展开更多
文摘We introduce a generalization of the Gorenstein injective modules:the Gorenstein FPn-injective modules(denoted by GI_(n)).They are the cycles of the exact complexes of injective modules that remain exact when we apply a functor Hom(A,-),with A any FP_(n)-injective module.Thus,GL_(o)is the class of classical Gorenstein injective modules,and GI_(1)is the class of Ding injective modules.We prove that over any ring R,for any n≥2,the class GI_(n)is the right half of a perfect cotorsion pair,and therefore it is an enveloping class.For n=1 we show that GI_(1)(i.e.,the Ding injectives)forms the right half of a hereditary cotorsion pair.If moreover the ring R is coherent,then the Ding injective modules form an enveloping class.We also define the dual notion,that of Gorenstein FP_(n)-projectives(denoted by GP_(n)).They generalize the Ding projective modules,and so,the Gorenstein projective modules.We prove that for any n≥2 the class GP_(n)is the left half of a complete hereditary cotorsion pair,and therefore it is special precovering.
基金Supported by National Natural Science Foundation of China(Grant No.11971225)。
文摘In this paper,we generalize the idea of Song,Zhao and Huang[Czechoslov.Math.J.,70,483±504(2020)]and introduce the notion of right(left)Gorenstein subcategory rg(l,∂)(lg(l,D)),relative to two additive full subcategoriesφand∂of an abelian category A.Under the assumption thatφ⊆∂,we prove that the right Gorenstein subcategory rg(l,D)possesses many nice properties that it is closed under extensions,kernels of epimorphisms and direct summands.Whenφ⊆Dandφ⊥D,we show that the right Gorenstein subcategory rg(l,D)admits some kind of stability.Then we discuss a resolution dimension for an object in A,called rg(l,D)-projective dimension.Finally,we prove that if(U,V)is a hereditary cotorsion pair with kernelφhas enough injectives,such that U⊆Dand U⊥∂,then(rg(l,D),φφ)is a weak Auslander±Buchweitz context,whereφis the subcategory of A consisting of objects with finiteφ-projective dimension.