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91.
In this note we first show that if H is a finite-dimensional Hopf algebra in a group Yetter-Drinfel'd category L^LyD(π) over a crossed Hopf group-coalgebra L, then its dual H^* is also a Hopf algebra in the category L^LyD(π). Then we establish the fundamental theorem of Hopf modules for H in the category L^LyD(π). 相似文献
92.
Nan GAO 《数学年刊B辑(英文版)》2009,30(3):231-238
The relative transpose via Gorenstein projective modules is introduced, and some corresponding results on the Auslander-Reiten sequences and the Auslander-Reiten formula to this relative version are generalized. 相似文献
93.
设u~(≥0)表示一个固定单李代数的半量子群,给出了u~(≥0)的性质和表示.证明了Hopf代数u~(≥0)不是拟余交换的,因此左u~(≥0)-模范畴不是辫子monoidal范畴.在权模范畴W中,给出了所有单对象和投射对象.最后描述了所有单的Yetter-Drinfel'd u~(≥0)-权模. 相似文献
94.
We investigate the simple modules for the sporadic simple Mathieu groups M22, M23 and M24 as well as those of the automorphism group, the covering groups and the bicyclic extensions of M22 in characteristics 2 and 3. We determine the vertices and sources as well as the Green correspondents of these simple modules. We also find two 3-blocks with elementary abelian defect groups of order 9 in these groups which are Morita equivalent to their Brauer correspondents. 相似文献
95.
Upasana Kashyap 《Journal of Functional Analysis》2009,256(11):3545-278
We prove that two dual operator algebras are weak∗ Morita equivalent in the sense of [D.P. Blecher, U. Kashyap, Morita equivalence of dual operator algebras, J. Pure Appl. Algebra 212 (2008) 2401-2412] if and only if they have equivalent categories of dual operator modules via completely contractive functors which are also weak∗-continuous on appropriate morphism spaces. Moreover, in a fashion similar to the operator algebra case, we characterize such functors as the module normal Haagerup tensor product with an appropriate weak∗ Morita equivalence bimodule. We also develop the theory of the W∗-dilation, which connects the non-selfadjoint dual operator algebra with the W∗-algebraic framework. In the case of weak∗ Morita equivalence, this W∗-dilation is a W∗-module over a von Neumann algebra generated by the non-selfadjoint dual operator algebra. The theory of the W∗-dilation is a key part of the proof of our main theorem. 相似文献
96.
Let (R, m) be a two-dimensional regular local ring and let A be a finitely generated torsion-free R-module. If A is a complete module, then Dan Katz and Vijay Kodiyalam show A satisfies five conditions. They ask whether these five conditions are equivalent without assuming A to be complete. In a previous paper we determined all implications among these five conditions with one exception. In this paper, with an additional hypothesis on the units of R, we resolve the remaining case. 相似文献
97.
In an earlier paper [8] the authors introduced strongly and properly semiprime modules. Here properly semiprime modules M are investigated under the condition that every cyclic submodule is M-projective (self-pp-modules). We study the idempotent closure of M using the techniques of Pierce stalks related to the central idempotents of the self-injective hull of M. As an application of our theory we obtain several results on (not necessarily associative) biregular, properly semiprime, reduced and Firings. An example is given of an associative semiprime PSP ring with polynomial identity which coincides with its central closure and is not biregular (see 3.6). Another example shows that a semiprime left and right FP-injective Pl-ring need not be regular (see 4.8). Some of the results were already announced in [7]. 相似文献
98.
A module M over a ring R is called a lifting module if every submodule A of M contains a direct summand K of M such that A/K is a small submodule of M/K (e.g., local modules are lifting). It is known that a (finite) direct sum of lifting modules need not be lifting. We prove that R is right Noetherian and indecomposable injective right R-modules are hollow if and only if every injective right R-module is a direct sum of lifting modules. We also discuss the case when an infinite direct sum of finitely generated modules containing its radical as a small submodule is lifting. 相似文献
99.
100.
Let M R be a right R-module over a ring R with S = End(M R ). We study the coherence of the left S-module S M relative to a hereditary torsion theory for the category of right R-modules. Various results are developed, many extending known results. 相似文献