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971.
Let G be a countable discrete group with an orthogonal representation α on a real Hilbert space H . We prove Lp Poincaré inequalities for the group measure space L∞(ΩH,γ)?G, where both the group action and the Gaussian measure space (ΩH,γ) are associated with the representation α . The idea of proof comes from Pisier?s method on the boundedness of Riesz transform and Lust-Piquard?s work on spin systems. Then we deduce a transportation type inequality from the Lp Poincaré inequalities in the general noncommutative setting. This inequality is sharp up to a constant (in the Gaussian setting). Several applications are given, including Wiener/Rademacher chaos estimation and new examples of Rieffel?s compact quantum metric spaces. 相似文献
972.
We analyze the local behavior of the Hausdorff centered measure for selfsimilar sets. If E is a self-similar set satisfying the open set condition, then Cs(E∩B(x,r)) ≤(2r)s for all x ∈ E and r 0, where Csdenotes the s-dimensional Hausdorff centered measure. The above inequality is used to obtain the upper bound of the Hausdorff centered measure. As the applications of above inequality, We obtained the upper bound of the Hausdorff centered measure for some self-similar sets with Hausdorff dimension equal to 1, and prove that the upper bound reach the exact Hausdorff centered measure. 相似文献
973.
记为非负单增函数且一阶偏导数均存.本文证明:(i)广义n参数Wiener过程(GBn)和广义n参数Ornstein-Uhlenbeck过程(广义OUPn)在D中导出的过程是马氏过程;(ii)如果GBn(或广义OUPn)在D中导出的过程成为某个GBk(或某个广义OUPk),则fj(t1…,tk)未必恒为正常数.(j=k+1,…,n). 相似文献
974.
We investigate bounds for point energies, separation radius, and mesh norm of certain arrangements of N points on sets A from a class of d-dimensional compact sets embedded in Rd′, 1dd′. We assume that these points interact through a Riesz potential V=|·|-s, where s>0 and |·| is the Euclidean distance in . With and denoting, respectively, the separation radius and mesh norm of s-extremal configurations, which are defined to yield minimal discrete Riesz s-energy, we show, in particular, the following.(A) For the d-dimensional unit sphere and s<d-1, and, moreover, if sd-2. The latter result is sharp in the case s=d-2. In addition, point energies for s-extremal configurations are asymptotically equal. This observation relates to numerical experiments on observed scar defects in certain biological systems.(B) For and s>d, and the mesh ratio is uniformly bounded for a wide subclass of . We also conclude that point energies for s-extremal configurations have the same order, as N→∞. 相似文献
975.
We prove the existence of real numbers badly approximated by rational fractions whose denominators form a sublacunar sequence. For example, for the ascending sequence s
n
, n = 1, 2, 3, ..., generated by the ordered numbers of the form 2i3j, i, j = 1, 2, 3, ..., we prove that the set of real numbers α such that inf
n∈ℕ
n‖s
n
α‖ > 0 is a set of Hausdorff dimension 1. The divergence of the series
implies that the Lebesgue measure of those numbers is zero.__________Translated from Matematicheskie Zametki, vol. 77, no. 6, 2005, pp. 803–813.Original Russian Text Copyright ©2005 by R. K. Akhunzhanov, N. G. Moshchevitin. 相似文献
976.
Ambar N. Sengupta 《Journal of Geometry and Physics》2003,47(4):398-426
We prove that integration over the moduli space of flat connections can be obtained as a limit of integration with respect to the Yang–Mills measure defined in terms of the heat-kernel for the gauge group. In doing this we also give a rigorous proof of Witten’s formula for the symplectic volume of the moduli space of flat connections. Our proof uses an elementary identity connecting determinants of matrices along with a careful accounting of certain dense subsets of full measure in the moduli space. 相似文献
977.
978.
在缺失数据机制是可忽略的假设下,导出了有单调缺失数据的条件独立正态模型中协方差阵和精度阵的Cholesky分解的最大似然估计和无偏估计.通过引入一类特殊的变换群并在更广义的损失下,获得了其最优同变估计.这表明最大似然估计和无偏估计是非容许的.最后,通过数值模拟验证了相关结果的有效性. 相似文献
979.
Given a bounded strongly pseudoconvex domain D in with smooth boundary, we characterize ‐Bergman Carleson measures for , , and . As an application, we show that the Bergman space version of the balayage of a Bergman Carleson measure on D belongs to BMO in the Kobayashi metric. 相似文献
980.
Luigi Manca 《随机分析与应用》2013,31(2):399-426
Abstract We consider stochastic semilinear partial differential equations with Lipschitz nonlinear terms. We prove existence and uniqueness of an invariant measure and the existence of a solution for the corresponding Kolmogorov equation in the space L 2(H;ν), where ν is the invariant measure. We also prove the closability of the derivative operator and an integration by parts formula. Finally, under boundness conditions on the nonlinear term, we prove a Poincaré inequality, a logarithmic Sobolev inequality, and the ipercontractivity of the transition semigroup. 相似文献