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991.
Bounding the Fitting height of a solvable group by the number of zeros in a character table 总被引:1,自引:0,他引:1
Guohua Qian 《Proceedings of the American Mathematical Society》2002,130(11):3171-3176
In this paper, we bound the Fitting height of a solvable group by the number of zeros in a character table.
992.
Michael Voit 《Journal of multivariate analysis》1996,59(2):230-248
Forn2, let (μxτ, n)τ0be the distributions of the Brownian motion on the unit sphereSn
n+1starting in some pointxSn. This paper supplements results of Saloff-Coste concerning the rate of convergence ofμxτ, nto the uniform distributionUnonSnforτ→∞ depending on the dimensionn. We show that,[formula]forτn:=(ln n+2s)/(2n), where erf denotes the error function. Our proof depends on approximations of the measuresμxτ, nby measures which are known explicitly via Poisson kernels onSn, and which tend, after suitable projections and dilatations, to normal distributions on
forn→∞. The above result as well as some further related limit results will be derived in this paper in the slightly more general context of Jacobi-type hypergroups. 相似文献
993.
The no-free-lunch theorem of optimization (NFLT) is an impossibility theorem telling us that a general-purpose, universal optimization strategy is impossible. The only way one strategy can outperform another is if it is specialized to the structure of the specific problem under consideration. Since optimization is a central human activity, an appreciation of the NFLT and its consequences is essential. In this paper, we present a framework for conceptualizing optimization that leads to a simple but rigorous explanation of the NFLT and its implications. 相似文献
994.
Brice Franke 《Journal of Theoretical Probability》2007,20(4):1087-1100
We prove a functional non-central limit theorem for jump-diffusions with periodic coefficients driven by stable Lévy-processes
with stability index α>1. The limit process turns out to be an α-stable Lévy process with an averaged jump-measure. Unlike in the situation where the diffusion is driven by Brownian motion,
there is no drift related enhancement of diffusivity. 相似文献
995.
研究利用Lie对称的生成元τ(t,q,q·)和ξs(t,q,q·)来构造广义H ojman守恒 量,并讨论三种特殊情况,研究表明:Hojman守恒量是该广义守恒量的特例,且在Lie对称 的生成元的形式为τ(t,q)和ξs(t,q)时,该广义Hojman守恒量可以导出Lu tzky守恒 量,此外,还给出一个排除平凡守恒量的条件.最后,给出两个简单例子,作为所获得结果 的说明.
关键词:
动力学系统
广义Hojman定理
Lie对称
守恒量 相似文献
996.
Quantum information processing is at the crossroads of physics, mathematics and computer science. It is concerned with what
we can and cannot do with quantum information that goes beyond the abilities of classical information processing devices.
Communication complexity is an area of classical computer science that aims at quantifying the amount of communication necessary
to solve distributed computational problems. Quantum communication complexity uses quantum mechanics to reduce the amount
of communication that would be classically required.
Pseudo-telepathy is a surprising application of quantum information processing to communication complexity. Thanks to entanglement,
perhaps the most nonclassical manifestation of quantum mechanics, two or more quantum players can accomplish a distributed
task with no need for communication whatsoever, which would be an impossible feat for classical players. After a detailed
overview of the principle and purpose of pseudo-telepathy, we present a survey of recent and not-so-recent work on the subject.
In particular, we describe and analyse all the pseudo-telepathy games currently known to the authors.
Supported in Part by Canada’s Natural Sciences and Engineering Research Council (NSERC), the Canada Research Chair programme
and the Canadian Institute for Advanced Research (CIAR).
Supported in part by a scholarship from Canada’s NSERC.
Supported in part by Canada’s NSERC
Québec’s Fonds de recherche sur la nature et les technologies (FQRNT), the CIAR and the Mathematics of Information Technology
and Complex Systems Network (MITACS). 相似文献
997.
牛文博 《数学年刊A辑(中文版)》2005,(6)
本文定义了单位过滤k-代数和非单位过滤k-代数的局部Hochschild同调和局部循环同调,给出 了它们之间的局部Connes长正合列.进一步利用循环同调来计算局部循环同调的短正合列公式,讨论 了关于过滤k-代数局部循环同调的切除定理. 相似文献
998.
LuCHUANRONG 《高校应用数学学报(英文版)》1997,12(4):375-380
Let(x1,j≥1)be a sequence of negatively associated random variables with ex1=o,ex^21<∞.in this paper a functional central limit theorem for negatively associated random variables under some conditions withbout stationarity is proved which is the same as the results for positively associated random variables. 相似文献
999.
我们在无限维空间中研究微分包含的生存W—单调轨道的存在性.基于Zorn引理,我们给出了一个逼近方法,在较弱的条件下得到了一个存在性定理,其特殊情形则包含了已有的生存定理和微分方程理论中的若干结果作为应用,我们首先研究了微分包含生存解的整体存在性,得到了整体生存理.然后我们研究了微分包含解的稳定性,得到一些新的结果. 相似文献
1000.
本文对“费尔马最后定理的证明”一文作出几点评注,主要结论是该证明仅仅是对费尔马最后定理的部分情形的证明,即并没有完全证明费尔马最后定理 相似文献