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排序方式: 共有1747条查询结果,搜索用时 17 毫秒
941.
WANG Dengyin Department of Mathematics China University of Mining Technology Xuzhou China 《中国科学A辑(英文版)》2005,48(6):808-818
With one exception, the holomorph of a finite dimensional abelian connected algebraic group is shown to be a complete generalized algebraic group. This result on algebraic group is an analogy to that on Lie algebra. 相似文献
942.
Stanisaw Betley 《K-Theory》2005,36(3-4):291-303
Assume that M is an R-bimodule. Let End(R, M) denotes the category whose objects are pairs (P, f), where P is a finitely generated projective right R-module and f: P → P ⊗ M. It has an exact structure obtained from the category of projectives over R by forgetting f s. We prove that, when R is a field, we have
denotes certain localization of the tensor algebra spanned by M. This result should be viewed as a special case of the noncommutative extension of the results of [4]. 相似文献
943.
Kayo Masuda Masayoshi Miyanishi 《Transactions of the American Mathematical Society》2005,357(12):4867-4883
We define affine pseudo-planes as one class of -homology planes. It is shown that there exists an infinite-dimensional family of non-isomorphic affine pseudo-planes which become isomorphic to each other by taking products with the affine line . Moreover, we show that there exists an infinite-dimensional family of the universal coverings of affine pseudo-planes with a cyclic group acting as the Galois group, which have the equivariant non-cancellation property. Our family contains the surfaces without the cancellation property, due to Danielewski-Fieseler and tom Dieck.
944.
设Pn(x)为[0,∞)上次数不超过n的代数多项式,则有‖p′n(x)e-x‖[0,∞)≤(6.3n+1)‖pn(x)e-x‖[0,∞).若pn(x)同时又是奇函数或偶函数,则有‖p′n(x)e-x‖[0,∞)≤(1.8+7n1/2)‖p相似文献
945.
一维时间相关的经典谐振子是一个SU(1,1) 非自治经典系统,物理上十分有用,而数学上难于得到其精确解析解. 首次把新颖的代数动力学方法用于经典动力学系统,得到了这个模型的一般精确解;当时间相关的弹性系数为某些初等函数时,给出了精确解的解析形式. 这是关于这一问题的重要结果. 从精确解出发,推导出最近文献中提出的"解析近似解",并指出该近似解的适用条件. 相似文献
946.
M. S. Raghunathan 《Proceedings Mathematical Sciences》1989,99(2):127-146
It is shown in this paper that ifG is the group ofk-points of a semisimple algebraic groupG over a local fieldk of positive characteristic such that all itsk-simple factors are ofk-rank 1 and Γ ⊂G is a non-cocompact irreducible lattice then Γ admits a fundamental domain which is a union of translates of Siegel domains.
As a consequence we deduce that ifG has more than one simple factor, then Γ is finitely generated and by a theorem due to Venkataramana, it is arithmetic. 相似文献
947.
948.
I. A. Chel’tsov 《Mathematical Notes》1997,62(3):377-389
Normal algebraic surfacesX with the property rk(Div(X)⊗ℚ/≡)=1, numerically ample canonical classes, and nonrational singularities are classified. It is proved, in particular,
that any such surfaceX is a contraction of an exceptional section of a (possibly singular) relatively minimal ruled surface
with a nonrational base. Moreover,
f is uniquely determined by the surfaceX.
Translated fromMatematicheskie Zametki, Vol. 62, No. 3, pp. 451–467, September, 1997.
Translated by O. V. Sipacheva 相似文献
949.
I. S. Krasil’shchik 《Acta Appl Math》1997,49(3):249-255
The Poincaré -lemma (stable triviality of Spencer cohomology groups) for smooth algebras is proved. 相似文献
950.
M. B. Bekka 《Proceedings of the American Mathematical Society》1998,126(2):507-514
The following results on uniqueness of invariant means are shown:
(i) Let be a connected almost simple algebraic group defined over . Assume that , the group of the real points in , is not compact. Let be a prime, and let be the compact -adic Lie group of the -points in . Then the normalized Haar measure on is the unique invariant mean on .
(ii) Let be a semisimple Lie group with finite centre and without compact factors, and let be a lattice in . Then integration against the -invariant probability measure on the homogeneous space is the unique -invariant mean on .