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71.
We prove the existence of uncountably many nonisomorphic topological projective planes, each universal in the sense that it contains an isomorphic copy of every pseudoline arrangement. 相似文献
72.
An analogue of Kattov's theorem on the equality between the dimension of a Tychonov space and the analytic dimension of its ring of bounded real-valued continuous maps is established for proximity spaces and proximally continuous maps by an internal method of proof. A new kind of filter, called proximally prime filter, arises naturally as a tool in this theory. 相似文献
73.
A. V. Pazhitnov 《K-Theory》1996,10(4):323-412
Let M be a closed connected smooth manifold with dim M=n6, and :
1(M) Z be an epimorphism. Denote by the group ring of
1(M) and let
–
be its Novikov completion. Let D
* be a free-based finitely generated chain complex over
–
. Assume that D
ii=0 for i1 and in–1 and that D
* has the same simple homotopy type as the Novikov-completed simplicial chain complex of the universal covering M. Let N be an integer. We prove that D
* can be realized, up to the terms of
–
of degree N as the Novikov complex of a Morse map : M S
1, belonging to . Applications to Arnold's conjectures and to the theory of fibering of M over S
1 are given. 相似文献
74.
John C. Baez 《Letters in Mathematical Physics》1996,38(2):129-143
Starting from a Lie group G whose Lie algebra is equipped with an invariant nondegenerate symmetric bilinear form, we show that four-dimensional BF theory with cosmological term gives rise to a TQFT satisfying a generalization of Atiyah's axioms to manifolds equipped with principal G-bundle. The case G=GL(4,) is especially interesting because every 4-manifold is then naturally equipped with a principal G-bundle, namely its frame bundle. In this case, the partition function of a compact oriented 4-manifold is the exponential of its signature, and the resulting TQFT is isomorphic to that constructed by Crane and Yetter using a state sum model, or by Broda using a surgery presentation of four-manifolds. 相似文献
75.
Reinhard Honegger 《Letters in Mathematical Physics》1993,27(3):191-203
By means of cocycle techniques in a recent paper, the global dynamics of mean field-boson couplings has been studied. Here, by restricting to the bosonic system the infinite time limit (t ) for very general initial states, one obtains time-asymptotic states on the bosonicC
*-Weyl algebra, in which one partially rediscovers the collective ordering of the infinite mean field lattice. 相似文献
76.
One more model of aq-harmonic oscillator based on theq-orthogonal polynomials of Al-Salam and Carlitz is discussed. The explicit form ofq-creation andq-annihilation operators,q-coherent states and an analog of the Fourier transformation are established. A connection of the kernel of this transform with a family of self-dual biorthogonal rational functions is observed. 相似文献
77.
A perturbation bound for the generalized polar decomposition 总被引:11,自引:0,他引:11
Ren-Cang Li 《BIT Numerical Mathematics》1993,33(2):304-308
LetA be anm×n complex matrix. A decompositionA=QH is termed ageneralized polar decomposition ofA ifQ is anm×n subunitary matrix (sometimes also called a partial isometry) andH a positive semidefinite Hermitian matrix. It was proved that a nonzero matrixA
m×n
has a unique generalized polar decompositionA=QH with the property (Q
H
)=(H), whereQ
H
denotes the conjugate transpose ofQ and (H) the column space ofH. The main result of this note is a perturbation bound forQ whenA is perturbed. 相似文献
78.
Parts of the results and the essential techniques of this note are taken from the Erlangen thesis (1991) of the second author. They were circulated as Nr. 122 of Schriftenreihe Komplexe Mannigfaltigkeiten. Our research was supported by DFG grant Ba 423/3-3 and the European Science Project Geometry of Algebraic Varieties SCI-0398-C(A) 相似文献
79.
Israel Gohberg Naum Krupnik Ilya Spitkovsky 《Integral Equations and Operator Theory》1993,17(3):322-337
The Banach algebra generated by one-dimensional linear singular integral operators with matrix valued piecewise continuous coefficients in the spaceL
p
(,) with an arbitrary weight is studied. The contour consists of a finite number of closed curves and open arcs with satisfy the Carleson condition. The contour may have a finite number of points of selfintersection. The symbol calculus in this algebra is the main result of the paper. 相似文献
80.
In this paper we prove local analyticity of solutions to the
-Neumann problem up to the boundary of rigid, completely decoupled pseudoconvex domains with real-analytic boundary. These
are domains that are locally of the form Imw > Σ |h
k
(z
k
)|2 with eachh
k
holomorphic and vanishing only at 0.
As in those earlier papers, we use purelyL
2 methods and must construct a special holomorphic vector fieldM and then use carefully balanced polynomials inM to localize high powers ofT = ∂/∂t effectively, wheret = Rew. 相似文献