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71.
Radu Miron 《Reports on Mathematical Physics》2004,54(2):131-147
The Randers spaces RFn were introduced by R. S. Ingarden. They are considered as Finsler spaces Fn = (M, α + β) equipped with the Cartan nonlinear connection. In the present paper we define and study what we call the Ingarden spaces, I Fn, as Finsler spaces I Fn = (M, α + β) equipped with the Lorentz nonlinear connection. The spaces R Fn and I Fn are completely different. For I Fn we discuss: the variational problem, Lorentz nonlinear connection, canonical N-metrical connection and its structure equations, the Cartan 1-form ω, the electromagnetic 2-form tF and the almost symplectic 2-form 0. The formula dω = F+θ is established. It has as a consequence the generalized Maxwell equations. Finally, the almost Hermitian model of I Fn is constructed. 相似文献
72.
Gaiane Panina 《Central European Journal of Mathematics》2006,4(2):270-293
Hyperbolic virtual polytopes arose originally as polytopal versions of counterexamples to the following A.D.Alexandrov’s uniqueness
conjecture: Let K ⊂ ℝ3
be a smooth convex body. If for a constant C, at every point of ∂K, we have R
1 ≤ C ≤ R
2
then K is a ball. (R
1
and R
2
stand for the principal curvature radii of ∂K.)
This paper gives a new (in comparison with the previous construction by Y.Martinez-Maure and by G.Panina) series of counterexamples
to the conjecture. In particular, a hyperbolic virtual polytope (and therefore, a hyperbolic hérisson) with odd an number
of horns is constructed.
Moreover, various properties of hyperbolic virtual polytopes and their fans are discussed. 相似文献
73.
V. S. Klimov 《Mathematical Notes》2007,81(1-2):61-71
We study homology characteristics of critical values and extremals of Lipschitz functionals defined on bounded closed convex subsets of a reflexive space that are invariant under deformations. Sufficient conditions for the existence of a bifurcation point of a multivalued potential operator (the switch principle for the typical number of an extremal) are established. 相似文献
74.
本篇文章首先定义了向量变分不等式的严格可行点概念,其次在假设了映射是强(D)-伪单调的情况下,证明了向量变分不等式解集非空有界与其严格可行点存在的等价性问题,推广了在数量变分不等式上得到的相应结果. 相似文献
75.
Henrik Stetkær 《Journal of Functional Analysis》2007,252(1):1-33
We extend results on square integrable representations of a locally compact group to subrepresentations of a representations induced from a character of a closed subgroup. We do so working in the framework of quotient representations of ∗-algebras. 相似文献
76.
In the present paper, we consider the problem of the optimal reconstruction of the solution of the wave equation from the approximate values of the Fourier coefficients of the function specifying the initial form of the string. For an operator defined on the weight space of vectors from l 2, we present the solution of the more general problem of reconstruction from the approximate values of the coordinates of these vectors. 相似文献
77.
78.
Fuzzy random vector is a measurable map from a probability space to a collection of fuzzy vectors. Our aim in this paper is
to discuss the measurability criteria for fuzzy random vectors, and show that under mild assumption, the measurability criteria
for upper semicontinuous fuzzy random vectors can be expressed in several different but equivalent formulations. Finally,
applying the obtained results, we resolve an open problem about the relationship between fuzzy random vectors and fuzzy random
variables. 相似文献
79.
J. -R. Chazottes P. Collet C. Külske F. Redig 《Probability Theory and Related Fields》2007,137(1-2):201-225
We present a new and simple approach to concentration inequalities in the context of dependent random processes and random
fields. Our method is based on coupling and does not use information inequalities. In case one has a uniform control on the
coupling, one obtains exponential concentration inequalities. If such a uniform control is no more possible, then one obtains
polynomial or stretched-exponential concentration inequalities. Our abstract results apply to Gibbs random fields, both at
high and low temperatures and in particular to the low-temperature Ising model which is a concrete example of non-uniformity
of the coupling.
相似文献
80.
Wei Gang SU Huai Jie ZHONG 《数学学报(英文版)》2006,22(2):515-522
This paper introduces the concept of the generalized Riesz operators and the concept of the generalized West decomposition of a general operator which generalizes the definition of the West decomposition of Riesz operators, and proves that the following three statements are equivalent on a general Banach space:
(a) Every generalized Riesz operator has the generalized West decomposition;
(b) Every operator makes strong Stampfli theorem true; Every operator has Apostol's compact correction. 相似文献