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421.
Siberian Mathematical Journal - We prove that every free nonabelian group has a finitely generated isolated subgroup not separable in the class of nilpotent groups. This enables us to give a... 相似文献
422.
结合环中的环的幂零性不是根性质。为此,本文将结合环中的幂零理想概念扩展为次拟幂零理想和拟幂零理想,定义次拟幂零根SN和拟幂零根QN,证明它们均为Amitsur-Kurosh根,且二者相等,进一步,我们给出了QN-半单环的构造命题和QN-根的模刻划。 相似文献
423.
Let be a field of characteristic zero. It is proved that a right symmetric nil-algebra of index n over is right nilpotent, and a Novikov nil-algebra of index n over is nilpotent. 相似文献
424.
Paulo Tirao 《Proceedings of the American Mathematical Society》2000,128(10):2875-2878
It is known that the total (co)-homoloy of a 2-step nilpotent Lie algebra is at least , where is the center of . We improve this result by showing that a better lower bound is , where and is a complement of in . Furthermore, we provide evidence that this is the best possible bound of the form .
425.
In this paper we establish an algebraic characterization of those infra-nilmanifolds modeled on a free c-step nilpotent Lie group and with an abelian holonomy group admitting an Anosov diffeomorphism. We also develop a new method for constructing examples of infra-nilmanifolds having an Anosov diffeomorphism. 相似文献
426.
Hulya Kadioglu 《Mathematical Methods in the Applied Sciences》2019,42(16):5390-5397
In this paper, we develop algorithmic approach to classify nilsoliton metrics on dimension 8. This approach includes finding eigenvalue type of the nilsoliton derivation, the nullity type, the index of the algebra. It can be considered as a continuation of our papers in Abstract and Applied analysis, volume 2013, 1 to 7, (2013), with article ID 871930, and in Journal of Symbolic Computation 50 (2013), 350 ‐ 373. In our previous work, we classified only ordered type, nilsoliton metric Lie algebras ie, the algebras with the derivation type (1 < 2 < 3… < n) in dimension 8 and 9. Here, we consider more general case. We consider such metrics with simple derivations on an indecomposable nilpotent Lie algebra. In one of our previous study, we have already classified nilsoliton metric Lie algebras with nonsingular Gram matrix in dimension 8 in Journal of Symbolic Computation, vol: 50, 350 ‐ 373, 2013. Here, we focus on the metrics with singular Gram matrix. We also develop faster algorithm in classifying such metrics. 相似文献
427.
VARIATIONS ON A THEME BY EULER 总被引:1,自引:0,他引:1
1.IntroductionAHallliltolliansystemofdifferentialequationsonRZnisgivedbyP~~H,(P,q),q=HP(P,q),(1)wherep=(pl,'.,P.),q=(ql,',q.)eR"arethegeneralizedcoordinatesandmolllentarespectivelyandH(P,q)istheellergyofthesystem.Thesystem(1)canberewrittenasthecompactf… 相似文献
428.
429.
Strichartz characterized eigenfunctions of the Laplacian on Euclidean spaces by boundedness conditions which generalized a result of Roe for the one-dimensional case. He also proved an analogous statement for the sub-Laplacian on the Heisenberg groups. In this paper, we extend this result to connected, simply connected two-step nilpotent Lie groups. 相似文献