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101.
Antonio M. Peralta 《Mathematische Zeitschrift》2001,237(3):531-545
We prove that given a real JB*-triple E, and a real Hilbert space H, then the set of those bounded linear operators T from E to H, such that there exists a norm one functional and corresponding pre-Hilbertian semi-norm on E such that
for all , is norm dense in the set of all bounded linear operators from E to H. As a tool for the above result, we show that if A is a JB-algebra and is a bounded linear operator then there exists a state such that
for all .
Received June 28, 1999; in final form January 28, 2000 / Published online March 12, 2001 相似文献
102.
Alexandre?MunnierEmail author 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2003,54(6):977-1000
This article deals with stability and small linear
oscillations of liquid bridges between fixed solid surfaces
(parallel plates, spheres, ...) under zero gravity. A general
investigation method for any kind of axisymmetric liquid bridge is
exposed but the author focus his work on the spherical liquid
bridge cases. In particular, he exposes a full theoretical study
of spherical liquid bridges between two spheres, plates and
cones. 相似文献
103.
We consider an Archimedean analogue of Tate's conjecture, and verify the conjecture in the examples of isospectral Riemann surfaces constructed by Vignéras and Sunada. We prove a simple lemma in group theory which lies at the heart of T. Sunada's theorem about isospectral manifolds. 相似文献
104.
Yurij M. Berezansky 《Integral Equations and Operator Theory》2002,44(3):255-289
The article is devoted to two generalizations of the classical power moment problem, namely: 1) instead of representing the moment sequence by 706v131v22/xxlarge955.gif" alt="lambda" align="BASELINE" BORDER="0">
n
, a representation by polynomialsP
n
(706v131v22/xxlarge955.gif" alt="lambda" align="BASELINE" BORDER="0">), 706v131v22/xxlarge8477.gif" alt="Ropf" align="BASELINE" BORDER="0">1, connected with a Jacobi matrix, appears; 2) in the representation, instead of 706v131v22/xxlarge955.gif" alt="lambda" align="BASELINE" BORDER="0">
n
, the expression 706v131v22/xxlarge955.gif" alt="lambda" align="BASELINE" BORDER="0">706v131v22/xxlarge8855.gif" alt="otimes" align="MIDDLE" BORDER="0">n
figures, where 706v131v22/xxlarge955.gif" alt="lambda" align="BASELINE" BORDER="0"> is a real generalized function (i.e., we investigate some infinite-dimensional moment problem).The work is partially supported by the DFG, Project 436 UKR 113/39/0 and by the CRDF, Project UM1-2090. 相似文献
105.
This is one in a series of papers studying measures of information in the so-called mixed theory of information (i.e. considering the events as well as their probabilities) on the open domain (i.e. without empty sets and zero probabilities). In this paper we find all-recursive, 3-semisymmetric inset entropies on the open domain. We do this by solving the fundamental equation of inset information of degree () on the open domain.Dedicated to Professor János Aczél on his 60th birthday. 相似文献
106.
Taeko Yamazaki 《Journal of Differential Equations》2005,210(2):290-316
We consider the initial (boundary) value problem for the Kirchhoff equations in exterior domains or in the whole space of dimension three, and show that these problems admit time-global solutions, provided the norms of the initial data in the usual Sobolev spaces of appropriate order are sufficiently small. We obtain uniform estimates of the L1(R) norms with respect to time variable at each point in the domain, of solutions of initial (boundary) value problem for the linear wave equations. We then show that the estimates above yield the unique global solvability for the Kirchhoff equations. 相似文献
107.
It is proved that a Lie algebra of compact operators with a non-zero Volterra ideal is reducible (has a nontrivial invariant subspace). A number of other criteria of reducibility for collections of operators is obtained. The results are applied to the structure theory of Lie algebras of compact operators and normed Lie algebras with compact adjoint action. 相似文献
108.
M. Daoulatli 《Journal of Differential Equations》2018,264(7):4260-4302
In this paper we study the behaviors of the energy of solutions of the wave equations with localized nonlinear damping in exterior domains. 相似文献
109.
In this paper, we apply the variational method with Structural Prescribed Boundary Conditions (SPBC) to prove the existence of periodic and quasi-periodic solutions for the planar four-body problem with two pairs of equal masses and . A path on satisfies the SPBC if the boundaries and , where A and B are two structural configuration spaces in and they depend on a rotation angle and the mass ratio .We show that there is a region such that there exists at least one local minimizer of the Lagrangian action functional on the path space satisfying the SPBC for any . The corresponding minimizing path of the minimizer can be extended to a non-homographic periodic solution if θ is commensurable with π or a quasi-periodic solution if θ is not commensurable with π. In the variational method with the SPBC, we only impose constraints on the boundary and we do not impose any symmetry constraint on solutions. Instead, we prove that our solutions that are extended from the initial minimizing paths possess certain symmetries.The periodic solutions can be further classified as simple choreographic solutions, double choreographic solutions and non-choreographic solutions. Among the many stable simple choreographic orbits, the most extraordinary one is the stable star pentagon choreographic solution when . Remarkably the unequal-mass variants of the stable star pentagon are just as stable as the equal mass choreographies. 相似文献
110.
Gangyong Lee Jae Keol Park S. Tariq Rizvi Cosmin S. Roman 《Journal of Pure and Applied Algebra》2018,222(9):2427-2455
Let V be a module with . V is called a quasi-Baer module if for each ideal J of S, for some . On the other hand, V is called a Rickart module if for each , for some . For a module N, the quasi-Baer module hull (resp., the Rickart module hull ) of N, if it exists, is the smallest quasi-Baer (resp., Rickart) overmodule, in a fixed injective hull of N. In this paper, we initiate the study of quasi-Baer and Rickart module hulls. When a ring R is semiprime and ideal intrinsic over its center, it is shown that every finitely generated projective R-module has a quasi-Baer hull. Let R be a Dedekind domain with F its field of fractions and let be any set of R-submodules of . For an R-module with , we show that has a quasi-Baer module hull if and only if is semisimple. This quasi-Baer hull is explicitly described. An example such that has no Rickart module hull is constructed. If N is a module over a Dedekind domain for which is projective and , where is the torsion submodule of N, we show that the quasi-Baer hull of N exists if and only if is semisimple. We prove that the Rickart module hull also exists for such modules N. Furthermore, we provide explicit constructions of and and show that in this situation these two hulls coincide. Among applications, it is shown that if N is a finitely generated module over a Dedekind domain, then N is quasi-Baer if and only if N is Rickart if and only if N is Baer if and only if N is semisimple or torsion-free. For a direct sum of finitely generated modules, where R is a Dedekind domain, we show that N is quasi-Baer if and only if N is Rickart if and only if N is semisimple or torsion-free. Examples exhibiting differences between the notions of a Baer hull, a quasi-Baer hull, and a Rickart hull of a module are presented. Various explicit examples illustrating our results are constructed. 相似文献