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81.
Alexander L. Rosenberg 《Communications in Mathematical Physics》1992,144(1):41-51
The goal of this work is to describe the irreducible representations of the quantum Heisenberg algebra and the unitary irreducible representation of one of its real forms. The solution of this problem is obtained through the investigation of theleft spectrum of the quantum Heisenberg algebra using the result about spectra of generic algebras of skew differential operators (cf. [R]). 相似文献
82.
Alexander Engström Patricia Hersh Bernd Sturmfels 《Rendiconti del Circolo Matematico di Palermo》1938,62(1):67-78
A toric cube is a subset of the standard cube defined by binomial inequalities. These basic semialgebraic sets are precisely the images of standard cubes under monomial maps. We study toric cubes from the perspective of topological combinatorics. Explicit decompositions as CW-complexes are constructed. Their open cells are interiors of toric cubes and their boundaries are subcomplexes. The motivating example of a toric cube is the edge-product space in phylogenetics, and our work generalizes results known for that space. 相似文献
83.
Alexander Goldenshluger 《Journal of multivariate analysis》2003,84(1):40-60
The problem of optimal prediction in the stochastic linear regression model with infinitely many parameters is considered. We suggest a prediction method that outperforms asymptotically the ordinary least squares predictor. Moreover, if the random errors are Gaussian, the method is asymptotically minimax over ellipsoids in ?2. The method is based on a regularized least squares estimator with weights of the Pinsker filter. We also consider the case of dynamic linear regression, which is important in the context of transfer function modeling. 相似文献
84.
85.
Nathalie Charton Achim Feldermann Alexander Theis Martina H. Stenzel Thomas P. Davis Christopher Barner‐Kowollik 《Journal of polymer science. Part A, Polymer chemistry》2004,42(21):5559-5559
The original article to which this Erratum refers was published in J Polym Sci Part A: Polym Chem (2004) 42(20) 5170–5179. No abstract. 相似文献
86.
87.
Alexander Dinghas 《Mathematische Annalen》1941,118(1):636-686
Ohne Zusammenfassung 相似文献
88.
Peter G. Casazza Ole Christensen Alexander M. Lindner Roman Vershynin 《Proceedings of the American Mathematical Society》2005,133(4):1025-1033
We show that the conjectured generalization of the Bourgain-Tzafriri restricted-invertibility theorem is equivalent to the conjecture of Feichtinger, stating that every bounded frame can be written as a finite union of Riesz basic sequences. We prove that any bounded frame can at least be written as a finite union of linearly independent sequences. We further show that the two conjectures are implied by the paving conjecture. Finally, we show that Weyl-Heisenberg frames over rational lattices are finite unions of Riesz basic sequences.
89.
Alexander A. Chernitskii 《Advances in Applied Clifford Algebras》2005,15(1):27-54
Space-time multivectors in Clifford algebra (space-time algebra) and their application to nonlinear electrodynamics are considered.
Functional product and infinitesimal operators for translation and rotation groups are introduced, where unit pseudoscalar
or hyperimaginary unit is used instead of imaginary unit. Basic systems of orthogonal functions (plane waves, cylindrical,
and spherical) for space-time multivectors are built by using the introduced infinitesimal operators. Appropriate orthogonal
decompositions for electromagnetic field are presented. These decompositions are applied to nonlinear electrodynamics. Appropriate
first order equation systems for cylindrical and spherical radial functions are obtained. Plane waves, cylindrical, and spherical
solutions to the linear electrodynamics are represented by using the introduced orthogonal functions. A decomposition of a
plane wave in terms of the introduced spherical harmonics is obtained. 相似文献
90.
Alexander Afriat 《Foundations of Physics Letters》2003,16(3):293-301
An abstract treatment of Bell inequalities in proposed, in which the parameters characterizing Bell's observable can be times rather than directions. The violation of a Bell inequality might then be taken to mean that a property of a system can be changed by the timing of a distant measurement, which could take place in the future. 相似文献