共查询到20条相似文献,搜索用时 31 毫秒
1.
Xiaohong Cao Maozheng Guo Bin Meng 《Proceedings of the American Mathematical Society》2005,133(10):2977-2984
The Kato spectrum of an operator is deployed to give necessary and sufficient conditions for Browder's theorem to hold.
2.
Xiaohong Cao 《Proceedings of the American Mathematical Society》2007,135(6):1701-1708
In this note, the relation between hypercyclic operator matrices (or supercyclic operator matrices) and the operator matrices which satisfy Weyl type theorems is discussed. Also, using a variant of the essential approximate point spectrum, we give the necessary and sufficient conditions for for which a-Browder's theorem or a-Weyl's theorem holds.
3.
In this paper,the author gives a new section theorem in L-convex spaces.And as its applications,the author proves a coincident theorem and a two-functional minimax theorem established in L-convex spaces. 相似文献
4.
Kevin Charles Jones Youngsoo Kim Andrea H. Mhoon Rekha Santhanam Barry J. Walker Daniel R. Grayson 《K-Theory》2004,32(2):181-191
We present a method for converting Theorem B style proofs in algebraic K-theory to Theorem A style proofs and apply it to the additivity theorem. 相似文献
5.
Stimulated by S. Ohta and W. Wylie, we establish some compactness theorems for complete Riemannian manifolds via m-Bakry–Émery and m-modified Ricci curvatures with negative m. Our results may be considered as generalizations of the classical compactness theorems via Ricci curvature due to S.B. Myers, W. Ambrose, G.J. Galloway, and J. Cheeger, M. Gromov, and M. Taylor, and relax some previous compactness criteria for complete Riemannian manifolds via m-Bakry–Émery and m-modified Ricci curvatures obtained when m is a positive constant or infinity. 相似文献
6.
In this paper, we introduce a multipermutation-based intersection theorem on the product space of several unit simplices, called the simplotope. This theorem gives a substantial generalization of an intersection result of Scarf on the unit simplex (Ref. 1). By using this new result, we also obtain a multipermutation-based generalization of the Brouwer fixed-point theorem on the simplotope. Furthermore, we apply this new result to an economic equilibrium model with indivisibilities and obtain an equilibrium existence theorem. 相似文献
7.
A∈B(H)称为是一个Drazin可逆的算子,若A有有限的升标和降标.用σ_D(A)={λ∈C:A-λI不是Drazin可逆的)表示Drazin谱集.本文证明了对于Hilbert空间上的一个2×2上三角算子矩阵M_C=■,从σ_D(A)∪σ_D(G)到σ_D(M_C)的道路需要从前面子集中移动σ_D(A)∩σ_D(B)中一定的开子集,即有等式:σ_D(A)∪σ_D(B)=σ_D(M_C)∪G,其中G为σ_D(M_C)中一定空洞的并,并且为σ_D(A)∪σ_D(B)的子集.2×2算子矩阵不一定满足Weyl定理,利用Drazin谱,我们研究了2×2上三角算子矩阵的Weyl定理,Browder定理,a-Weyl定理和a-Browder定理. 相似文献
8.
9.
Mihály Bessenyei 《Indagationes Mathematicae》2018,29(3):873-877
The aim of this note is to characterize in terms of inequalities those pairs of real functions (acting on a convex subset of a vector space) that possess an affine separator. The main result is originally due to Behrends and Nikodem. Their method is based on the Hahn–Banach Theorem and a variant of the Helly Theorem. In our approach, a direct and independent proof is presented via the Radon and the Helly Theorems. 相似文献
10.
Minki Kim 《Discrete Mathematics》2017,340(1):3167-3170
Helly’s theorem is a classical result concerning the intersection patterns of convex sets in . Two important generalizations are the colorful version and the fractional version. Recently, Bárány et al. combined the two, obtaining a colorful fractional Helly theorem. In this paper, we give an improved version of their result. 相似文献
11.
在G-凸空间中证明了一些新的KKM型定理.作为应用,在G-凸空间中得到了一些新的匹配定理和截口定理,所得结果改进和推广了[2,3,7]中的相关结果. 相似文献
12.
Xiaohong Cao 《Journal of Mathematical Analysis and Applications》2006,320(2):795-803
Using the new spectrum set defined in this note, we give the necessary and sufficient condition for T which the Weyl's theorem holds. We also consider how the Weyl's theorem survives for analytically Class A operators. 相似文献
13.
Weyl spectra and Weyl's theorem 总被引:1,自引:0,他引:1
Xiaohong Cao Maozheng Guo Bin Meng 《Journal of Mathematical Analysis and Applications》2003,288(2):758-767
Two variants of the Weyl spectrum are discussed. We find, for example, that if one of them coincides with the Browder spectrum then Weyl's theorem holds, and conversely for isoloid operators. 相似文献
14.
本文通过定义新的谱集,给出了算子满足a-Browder定理和a-Weyl定理的充要条件,运用了文章中新定义的谱集,研究了解析hyponormal算子的a-Weyl定理. 相似文献
15.
Tedja Santanoe Oepomo 《数学物理学报(B辑英文版)》2011,31(3):1189-1202
This paper describes a new method and algorithm for the numerical solution of eigenvalues with the largest real part of positive matrices.The method is based on a numerical implementation of Collatz’s eigenvalue inclusion theorem for non-negative irreducible matrices.Eigenvalues are analyzed for the studies of the stability of linear systems.Finally, a numerical discussion is given to derive the required number of mathematical operations of the new algorithm. Comparisons between the new algorithm and several well known ones, such as Power, and QR methods, are discussed. 相似文献
16.
We here study the Brill-Noether theory for rank two vector bundles generated by their sections. We generalize the vanishing theorem, the Clifford theorem and the existence theorem to such bundles. 相似文献
17.
FC-空间上的鞍点定理及应用 总被引:1,自引:0,他引:1
在不具有任何凸性结构和线性结构的有限连续空间(简称FC-空间)中给出了一个鞍点定理.并应用此定理,在很弱的条件下证明了一些非空交定理及截口定理,推广了近期文献中的一些相关的结果. 相似文献
18.
本文通过定义新的谱集,给出了算子满足a-Browder定理和a-Weyl定理的充要条件,运用了文章中新定义的谱集,研究了解析hyponormal算子的a-Weyl定理. 相似文献
19.
Kyriakos Kontostathis 《Mathematical Logic Quarterly》1992,38(1):189-195
We formulate an abstract version of the finite injury method in the form of the Baire category theorem. The theorem has the following corollaries: The Friedberg-Muchnik pair of recursively enumerable degrees, the Sacks splitting theorem, the existence of a minimal degree below 0′ and the Shoenfield jump theorem. 相似文献
20.
超凸空间中的连续选择定理与耦合定理 总被引:14,自引:0,他引:14
本文给出了超凸空间中的连续选择定理与耦合定理,并得到了它们的证明,作为应用,我们给出了超凸空间中的不动点定理与截口定理. 相似文献