Using a tunable clustering coeffcient model withoutchanging the degree distribution, we investigate the effect of clustering coefficient on synchronization of networks with both unweighted and weighted couplings. For ...Using a tunable clustering coeffcient model withoutchanging the degree distribution, we investigate the effect of clustering coefficient on synchronization of networks with both unweighted and weighted couplings. For several typical categories of complex networks, the more triangles are in the networks, the worse the synchronizability of the networks is.展开更多
We introduce a class of categories, called clustered hyperbolic categories, which are constructed from a categorized version of preseeds called categorical preseeds using categorical mutations that are a "functorial...We introduce a class of categories, called clustered hyperbolic categories, which are constructed from a categorized version of preseeds called categorical preseeds using categorical mutations that are a "functorial" edition of preseed mutations. Every Weyl preseed p gives rise to a categorical preseed P which generates a clustered hyperbolic category; this is formed by copies of categories each one of which is equivalent to the category of representations of the Weyl cluster algebra H(p). A "categorical realization" of Weyl cluster algebra is provided in the sense of defining a map Fp from any clustered hyperbolic category induced from p to the Weyl cluster algebra H(p), where the image of Fp generates H(p).展开更多
Relations between Corenstein derived categories, Gorenstein defect categories and Gorenstein stable categories are established. Using these, the Gorensteinness of an algebra A and invariants with respect to recolle- m...Relations between Corenstein derived categories, Gorenstein defect categories and Gorenstein stable categories are established. Using these, the Gorensteinness of an algebra A and invariants with respect to recolle- ments of the bounded Gorenstein derived category Dgbp(A-mod) of A are investigated. Specifically, the Goren- steinness of A is characterized in terms of recollements of Dbp(A-mod) and Corenstein derived equivalences. It is also shown that Cohen-Macaulay-finiteness is invariant with respect to the recollements of D^p(A-mod).展开更多
There are various adjunctions between model(co)slice categories. The author gives a proposition to characterize when these adjunctions are Quillen equivalences. As an application, a triangle equivalence between the st...There are various adjunctions between model(co)slice categories. The author gives a proposition to characterize when these adjunctions are Quillen equivalences. As an application, a triangle equivalence between the stable category of a Frobenius category and the homotopy category of a non-pointed model category is given.展开更多
With the purpose of providing a categorical treatment of weak multiplier bialgebras (introduced by BShm, Gomez-Torrecillas and Ldpez-Centella in 2015), an ap- propriate notion of morphism for these algebraic objects...With the purpose of providing a categorical treatment of weak multiplier bialgebras (introduced by BShm, Gomez-Torrecillas and Ldpez-Centella in 2015), an ap- propriate notion of morphism for these algebraic objects is proposed. This allows us to define a category wmb of (regular) weak multiplier bialgebras (with a right full comultipli- cation), containing as a full subcategory the category wba of weak bialgebras defined by BShm, Gomez-Torrecillas and Lopez-Centella in 2014. We present a great source of ex- amples of these morphisms proving that, under some assumption, a functor between small categories induces a morphism of this kind between the natural weak multiplier bialgebra structures carried by the linear spans of the arrow sets of the categories. We explore the notion of elements of group-like type in a weak multiplier bialgebra, proposing a definition in the line of the one by the aforementioned authors for weak bialgebras. We show a big number of its properties and provide more general versions of many results known in the context of weak bialgebras. In particular, in analogy with the classical bialgebra setting (where the set of group-like elements is a monoid), we prove that the set of these elements possesses a structure of category.展开更多
Let A be a finite-dimensional algebra over an algebraically closed field k,ε the category of all exact sequences in A-rood, Mp (respectively, Ml) the full subcategory of C consisting of those objects with projecti...Let A be a finite-dimensional algebra over an algebraically closed field k,ε the category of all exact sequences in A-rood, Mp (respectively, Ml) the full subcategory of C consisting of those objects with projective (respectively, injective) middle terms. It is proved that Mp (respectively, MI) is contravariantly finite (respectively, covariantly finite) in ε. As an application, it is shown that Mp = MI is functorially finite and has Auslander-Reiten sequences provided A is selfinjective. Keywords category of exact sequences, contravariantly finite subcategory, functorially finite subcategory Auslander-Reiten sequences, selfinjective algebra展开更多
基金The project partly supported by National Natural Science Foundation for Distinguished Young Scholars of China under Grant No. 60225013, National Natural Science Foundation of China under Grants Nos. 70271072, 70431002, and 90412004, and Shanghai RisingStar Program under Grant No.05QMX1436Author (X. Li) also acknowledges the support from the Alexander von Humboldt Foundation.
文摘Using a tunable clustering coeffcient model withoutchanging the degree distribution, we investigate the effect of clustering coefficient on synchronization of networks with both unweighted and weighted couplings. For several typical categories of complex networks, the more triangles are in the networks, the worse the synchronizability of the networks is.
文摘We introduce a class of categories, called clustered hyperbolic categories, which are constructed from a categorized version of preseeds called categorical preseeds using categorical mutations that are a "functorial" edition of preseed mutations. Every Weyl preseed p gives rise to a categorical preseed P which generates a clustered hyperbolic category; this is formed by copies of categories each one of which is equivalent to the category of representations of the Weyl cluster algebra H(p). A "categorical realization" of Weyl cluster algebra is provided in the sense of defining a map Fp from any clustered hyperbolic category induced from p to the Weyl cluster algebra H(p), where the image of Fp generates H(p).
基金supported by National Natural Science Foundation of China (Grant No. 11101259)
文摘Relations between Corenstein derived categories, Gorenstein defect categories and Gorenstein stable categories are established. Using these, the Gorensteinness of an algebra A and invariants with respect to recolle- ments of the bounded Gorenstein derived category Dgbp(A-mod) of A are investigated. Specifically, the Goren- steinness of A is characterized in terms of recollements of Dbp(A-mod) and Corenstein derived equivalences. It is also shown that Cohen-Macaulay-finiteness is invariant with respect to the recollements of D^p(A-mod).
基金supported by Jiangsu Normal University(No.JSNU12XLR025)
文摘There are various adjunctions between model(co)slice categories. The author gives a proposition to characterize when these adjunctions are Quillen equivalences. As an application, a triangle equivalence between the stable category of a Frobenius category and the homotopy category of a non-pointed model category is given.
文摘With the purpose of providing a categorical treatment of weak multiplier bialgebras (introduced by BShm, Gomez-Torrecillas and Ldpez-Centella in 2015), an ap- propriate notion of morphism for these algebraic objects is proposed. This allows us to define a category wmb of (regular) weak multiplier bialgebras (with a right full comultipli- cation), containing as a full subcategory the category wba of weak bialgebras defined by BShm, Gomez-Torrecillas and Lopez-Centella in 2014. We present a great source of ex- amples of these morphisms proving that, under some assumption, a functor between small categories induces a morphism of this kind between the natural weak multiplier bialgebra structures carried by the linear spans of the arrow sets of the categories. We explore the notion of elements of group-like type in a weak multiplier bialgebra, proposing a definition in the line of the one by the aforementioned authors for weak bialgebras. We show a big number of its properties and provide more general versions of many results known in the context of weak bialgebras. In particular, in analogy with the classical bialgebra setting (where the set of group-like elements is a monoid), we prove that the set of these elements possesses a structure of category.
基金supported by National Natural Science Foundation of China(Grant No.11271257)National Science Foundation of Shanghai Municiple(Granted No.13ZR1422500)
文摘Let A be a finite-dimensional algebra over an algebraically closed field k,ε the category of all exact sequences in A-rood, Mp (respectively, Ml) the full subcategory of C consisting of those objects with projective (respectively, injective) middle terms. It is proved that Mp (respectively, MI) is contravariantly finite (respectively, covariantly finite) in ε. As an application, it is shown that Mp = MI is functorially finite and has Auslander-Reiten sequences provided A is selfinjective. Keywords category of exact sequences, contravariantly finite subcategory, functorially finite subcategory Auslander-Reiten sequences, selfinjective algebra