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991.
We show that the r-dominated polynomials on p(2 p ) are integral on 1, and give examples proving that the converse is not true. We characterize when the 2-homogeneous, diagonal polynomials on p(1 < p ) are r-dominated. We prove that, unlike the linear case, there are nuclear polynomials which are not 1-dominated.Received: 6 June 2004; revised: 28 September 2004 相似文献
992.
D. A. Edwards 《Archiv der Mathematik》2005,84(6):559-567
Suppose that X is a topological space with preorder , and that –g, f are bounded upper semicontinuous functions on X such that g(x) f(y) whenever x y. We consider the question whether there exists a bounded increasing continuous function h on X such that g h f, and obtain an existence theorem that gives necessary and sufficient conditions. This result leads to an extension theorem giving conditions that allow a bounded increasing continuous function defined on an open subset of X to be extended to a function of the same type on X. The application of these results to extremally disconnected locally compact spaces is studied.Received: 26 May 2004 相似文献
993.
E. Kowalski 《Archiv der Mathematik》2005,84(1):57-70
We consider the problem of distinguishing two modular forms, or two elliptic curves, by looking at the coefficients of their L-functions for small primes (compared to their conductor). Using analytic methods based on large-sieve type inequalities we give various upper bounds on the number of forms having the first few coefficients equal to those of a fixed one. In addition, we consider similar questions of recognizing symmetric squares and CM forms from the behavior of small primes.Received: 30 August 2004 相似文献
994.
Markus Schmidmeier 《Archiv der Mathematik》2005,84(5):392-397
995.
Yasutsugu Fujita 《manuscripta mathematica》2005,118(3):339-360
Let E be an elliptic curve over Q and p a prime number. Denote by Qp,∞ the Zp-extension of Q. In this paper, we show that if p≠3, then where E(Qp,∞)(2) is the 2-primary part of the group E(Qp,∞) of Qp,∞-rational points on E. More precisely, in case p=2, we completely classify E(Q2,∞)(2) in terms of E(Q)(2); in case p≥5 (or in case p=3 and E(Q)(2)≠{O}), we show that E(Qp,∞)(2)=E(Q)(2). 相似文献
996.
A basic integral equation of random fields estimation theory by the criterion of minimum of variance of the estimation error is of the form Rh = f, where
and R(x, y) is a covariance function.The singular perturbation problem we study consists of finding the asymptotic behavior of the solution to the equation
as
0.$$" align="middle" border="0">
The domain D can be an interval or a domain in Rn, n > 1. The class of operators R is defined by the class of their kernels R(x,y) which solve the equation Q(x, Dx)R(x, y) = P(x, Dx)δ(x − y), where Q(x, Dx) and Px, Dx) are elliptic differential operators. 相似文献
997.
Yurij M. Berezansky Eugene W. Lytvynov Artem D. Pulemyotov 《Integral Equations and Operator Theory》2005,53(2):191-208
By definition, a Jacobi field
is a family of commuting selfadjoint three-diagonal operators in the Fock space
The operators J(ϕ) are indexed by the vectors of a real Hilbert space H+. The spectral measure ρ of the field J is defined on the space H− of functionals over H+. The image of the measure ρ under a mapping
is a probability measure ρK on T−. We obtain a family JK of operators whose spectral measure is equal to ρK. We also obtain the chaotic decomposition for the space L2(T−, dρ K). 相似文献
998.
Laurent?DenisEmail author Anis?Matoussi Lucretiu?Stoica 《Probability Theory and Related Fields》2005,133(4):437-463
In this paper we prove Lp estimates (p≥2) for the uniform norm of the paths of solutions of quasilinear stochastic partial differential equations (SPDE) of parabolic
type. Our method is based on a version of Moser's iteration scheme developed by Aronson and Serrin in the context of non-linear
parabolic PDE. 相似文献
999.
We obtain explicit generators for the centre of the Ringel-Hall algebra of a cyclic quiver and define a canonical algebra
monomorphism from Macdonald's ring of symmetric functions to the centre, which furthermore respects the comultiplication and
the symmetric bilinear form.
Dedicated to Claus Michael Ringel on the occasion of his 60th birthday 相似文献
1000.
Let R be a commutative noetherian henselian non-Gorenstein local ring of depth zero. Denote by modR the category of all finitely generated R-modules, and by the full subcategory of modR consisting of all R-modules of Gorenstein dimension zero. We prove in this paper that if contains a non-free module, then it is not precovering in modR, in particular, there exist infinitely many isomorphism classes of indecomposable R-modules of Gorenstein dimension zero. 相似文献