• Title/Summary/Keyword: H-compact

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A NOTE ON H-SETS

  • Tikoo, Mohan L.
    • Kyungpook Mathematical Journal
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    • v.28 no.1
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    • pp.91-95
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    • 1988
  • The nature of a H-set in a Hausdorff space is not well understood. In this note it is shown that if X is a countable union of nowhere dense compact sets, then X is not H-embeddable in any Hausdorff space. An example is given to show that there exists a non-Urysohn, non-H-closed space X such that each H-set of X is compact.

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ABSTRACT HARMONIC ANALYSIS OVER SPACES OF COMPLEX MEASURES ON HOMOGENEOUS SPACES OF COMPACT GROUPS

  • Farashahi, Arash Ghaani
    • Bulletin of the Korean Mathematical Society
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    • v.54 no.4
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    • pp.1229-1240
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    • 2017
  • This paper presents a systematic study of the abstract harmonic analysis over spaces of complex measures on homogeneous spaces of compact groups. Let G be a compact group and H be a closed subgroup of G. Then we study abstract harmonic analysis of complex measures over the left coset space G/H.

COMPACT INTERPOLATION ON AX = Y IN ALG𝓛

  • Kang, Joo Ho
    • Journal of applied mathematics & informatics
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    • v.32 no.3_4
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    • pp.441-446
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    • 2014
  • In this paper the following is proved: Let $\mathcal{L}$ be a subspace lattice on a Hilbert space $\mathcal{H}$ and X and Y be operators acting on $\mathcal{H}$. Then there exists a compact operator A in $Alg\mathcal{L}$ such that AX = Y if and only if ${\sup}\{\frac{{\parallel}E^{\perp}Yf{\parallel}}{{\parallel}E^{\perp}Xf{\parallel}}\;:\;f{\in}\mathcal{H},\;E{\in}\mathcal{L}\}$ = K < ${\infty}$ and Y is compact. Moreover, if the necessary condition holds, then we may choose an operator A such that AX = Y and ${\parallel}A{\parallel}=K$.

ON THE ELLIPTIC EQUATION ${\Delta}u+H({\chi})e^{u}$ = 0 ON COMPACT MANIFOLDS

  • Jung, Yoon-Tae;Kim, Seon-Bu;Shin, Cheol-Guen
    • The Pure and Applied Mathematics
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    • v.3 no.1
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    • pp.9-18
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    • 1996
  • In this paper, we consider the existence of a solution to the elliptic nonlinear partial differential equation ${\Delta}u+H({\chi})e^{u}$ = 0 (H $\neq$ 0) (1) on a compact manifold without boundary. This equation is related to the problem of a pointwise conformal deformation of metrics on two dimensional compact connected manifolds.(omitted)

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COMPACT INTERPOLATION ON AX = Y IN A TRIDIAGONAL ALGEBRA ALGL

  • Kang, Joo-Ho
    • Journal of applied mathematics & informatics
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    • v.19 no.1_2
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    • pp.447-452
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    • 2005
  • Given operators X and Y on a Hilbert space H, an interpolating operator is a bounded operator A such that AX = Y. In this article, we investigate compact interpolation problems for vectors in a tridiagonal algebra. Let L be a subspace lattice acting on a separable complex Hilbert space H and Alg L be a tridiagonal algebra. Let X = $(x_{ij})\;and\;Y\;=\;(y_{ij})$ be operators acting on H. Then the following are equivalent: (1) There exists a compact operator A = $(x_{ij})$ in AlgL such that AX = Y. (2) There is a sequence {$\alpha_n$} in $\mathbb{C}$ such that {$\alpha_n$} converges to zero and $$y_1\;_j=\alpha_1x_1\;_j+\alpha_2x_2\;_j\;y_{2k}\;_j=\alpha_{4k-1}x_{2k\;j}\;y_{2k+1\;j}=\alpha_{4k}x_{2k\;j}+\alpha_{4k+1}x_{2k+1\;j}+\alpha_{4k+2}x_{2k+2\;j\;for\;all\;k\;\epsilon\;\mathbb{N}$$.

HOMOTOPY FIXED POINT SET OF THE HOMOTOPY FIBRE

  • Lee, Hyang-Sook
    • Bulletin of the Korean Mathematical Society
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    • v.36 no.4
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    • pp.755-762
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    • 1999
  • Let X be a p-compace groyp, Y -> X bd a p-compact-subgroup of X and G -> X be a p-compact toral subgroup of X with $(X/Y)^{hG} \neq 0$. In this paper we show that the homotopy fixed point set of the homotopy fibre $(X/Y)^{hG}$ is $F_p$-finite.

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GENERALIZED WEYL'S THEOREM FOR FUNCTIONS OF OPERATORS AND COMPACT PERTURBATIONS

  • Zhou, Ting Ting;Li, Chun Guang;Zhu, Sen
    • Bulletin of the Korean Mathematical Society
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    • v.49 no.5
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    • pp.899-910
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    • 2012
  • Let $\mathcal{H}$ be a complex separable infinite dimensional Hilbert space. In this paper, a necessary and sufficient condition is given for an operator T on $\mathcal{H}$ to satisfy that $f(T)$ obeys generalized Weyl's theorem for each function $f$ analytic on some neighborhood of ${\sigma}(T)$. Also we investigate the stability of generalized Weyl's theorem under (small) compact perturbations.