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211.
For the unfolding of equivariant bifurcation problems with two types of state variables in the presence of parameter symmetry,the versal unfolding theorem with respect to left-right equivalence is obtained by using the related methods and techniques in the singularity theory of smooth map-germs.The corresponding results in[4,9]can be considered as its special cases.A relationship between the versal unfolding w.r.t.left-right equivalence and the versal deformation w.r.t.contact equivalence is established. 相似文献
212.
Curved multi-dimensional space-times (5D and higher) are constructed by embedding them in one higher-dimensional flat space. The condition that the embedding coordinates have a separable form, plus the demand of an orthogonal resulting space-time, implies that the curved multi-dimensional space-time has 4D de-Sitter subspaces (for constant extra-dimensions) in which the 3D subspace has an accelerated expansion. A complete determination of the curved multi-dimensional spacetime geometry is obtained provided we impose a new type of “equivalence principle”, meaning that there is a geodesic which from the embedding space has a rectliniar motion. According to this new equivalence principle, we can find the extra-dimensions metric components, each curved multi-dimensional spacetime surface’s equation, the energy-momentum tensors and the extra-dimensions as functions of a scalar field. The generic geodesic in each 5D spacetime are studied: they include solutions where particle’s motion along the extra-dimension is periodic and the 3D expansion factor is inflationary (accelerated expansion). Thus, the 3D subspace has an accelerated expansion. 相似文献
213.
Phantom Maps from a Strong Homology Viewpoint 总被引:1,自引:0,他引:1
Dae Woong LEE 《数学学报(英文版)》2006,22(3):711-718
Let X and Y be connected nilpotent CW-complexes of finite type. In this paper we deal with another complete analysis of a set of phantom maps in terms of strong homology by using the derived functors. We also prove that the set of homotopy classes of maps is independent of the choice of both rational homotopy equivalent classes and completion genera. 相似文献
214.
n级三角矩阵环上的模范畴和同调特征 总被引:1,自引:0,他引:1
本文给出了n级三角矩阵环Гn的定义.证明了n级三角矩阵代数Гn上的有限生成模范畴mod Гn与范畴Гn(?)等价,得到了诸如Гn的Jacobson根,Гn(?)的不可分解投射对象的形式及Гn的整体维数等性质. 相似文献
215.
W. Kucharz 《Geometriae Dedicata》2004,106(1):113-122
In this paper we study algebraic cycles on smooth quasiprojective real algebraic varieties. We are interested under what conditions an algebraic cycle homologous to zero is rationally equivalent to a cycle supporting no real points. 相似文献
216.
《Journal of Pure and Applied Algebra》2022,226(12):107131
We define the notion of isosingular loci of algebraic varieties, following the analytic case first studied by Ephraim. These are subsets of points where the variety has a prescribed formal singularity type. We show that the isosingular loci of an algebraic variety are locally closed in the Zariski topology and the associated reduced subschemes are smooth. Moreover, assuming characteristic 0, we prove the existence of a decomposition of the formal neighborhoods at closed points into a product of the respective isosingular locus at that point and a smooth factor. One of the main obstructions in the positive characteristic case is the non-separability of the orbit map associated to the contact group, as first observed by Greuel and Pham for isolated singularities. 相似文献
217.
设q为质数幂,m为大于1的正整数,p_(1),p_(2)为不同的奇质数满足gcd(q,p_(1)p_(2))=1且m|gcd(p_(1)-1,p_(2)-1).本文基于m次剩余的思想,给出码长为p_(1)p_(2)的m次剩余码的两种构造.对每种构造,分别给出其为
相似文献
218.
Let be an infinitely divisible probability measure onR
n
without Gaussian component and let be its Lévy measure. Suppose that is absolutely continuous with respect to the Lebesgue measure . We investigate the structure of the set
n
of admissible translates of . This yields a unified presentation of previously known results. We also show that if(S)>0 then is equivalent to , under the assumption that supp =R
n
, whereS is the closure of the semigroup generated by the support of .The research of this author is supported by KBN Grant.The research of this author is supported by AFSOR Grant No. 90-0168, and the University of Tennessee Science Alliance, a State of Tennessee Center of Excellence. 相似文献
219.
Ruy Exel 《K-Theory》1993,7(3):285-308
GivenC*-algebrasA andB and an imprimitivityA-B-bimoduleX, we construct an explicit isomorphismX
*:K
i
(A)K
i
(B), whereK
i
denotes the complexK-theory functors fori=0, 1. Our techniques do not require separability nor the existence of countable approximate identities. We thus extend to generalC*-algebras the result of Brown, Green, and Rieffel according to which, strongly Morita equivalentC*-algebras have isomorphicK-groups. The method employed includes a study of Fredholm operators on Hilbert modules.On leave from the University of São Paulo, Brazil. 相似文献
220.
Maud Brink 《光谱学快报》2013,46(2):123-130
The double magnetic non equivalence of the diastereotopic methylene protons resp. geminal methyl groups of 2-substituted 1,6-methano [10]annulenes were observed in five solvents. It was found that ΔνAB for one of the two methylene groups were much smaller than ΔνA ‘B’ for the other and that ΔνA‘B’ was much more solvent dependent than ΔνAB. ΔνA “B” for the bridge protons varied very little with the solvent used. 相似文献