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http://dx.doi.org/10.5666/KMJ.2014.54.2.157

A Cyclic Subnormal Completion of Complex Data  

Jung, Il Bong (Department of Mathematics, Kyungpook National University)
Li, Chunji (Institute of System Science, Northeastern University)
Park, Sun Hyun (Department of Mathematics, Kyungpook National University)
Publication Information
Kyungpook Mathematical Journal / v.54, no.2, 2014 , pp. 157-163 More about this Journal
Abstract
For a finite subset ${\Lambda}$ of $\mathbb{N}_0{\times}\mathbb{N}_0$, where $\mathbb{N}_0$ is the set of nonnegative integers, we say that a complex data ${\gamma}_{\Lambda}:=\{{\gamma}_{ij}\}_{(ij){\in}{\Lambda}}$ in the unit disc $\mathbf{D}$ of complex numbers has a cyclic subnormal completion if there exists a Hilbert space $\mathcal{H}$ and a cyclic subnormal operator S on $\mathcal{H}$ with a unit cyclic vector $x_0{\in}\mathcal{H}$ such that ${\langle}S^{*i}S^jx_0,x_0{\rangle}={\gamma}_{ij}$ for all $i,j{\in}\mathbb{N}_0$. In this note, we obtain some sufficient conditions for a cyclic subnormal completion of ${\gamma}_{\Lambda}$, where ${\Lambda}$ is a finite subset of $\mathbb{N}_0{\times}\mathbb{N}_0$.
Keywords
subnormal completion; cyclic vector; truncated moment matrix; flat extension;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
1 R. Curto and L. Fialkow, Flat extensions of positive moment matrices: recursively generated relations, Memoirs Amer. Math. Soc., 648(1998).
2 M. Embry, A generalization of the Halmos-Bram criterion for subnormality, Acta. Sci. Math., (Szeged) 31(1973), 61-64.
3 I. B. Jung, C. Li, and S. Park, Complex moment matrices via Halmos-Bram and Embry conditions, J. Korean Math. Soc., 44(2007), 949-970.   과학기술학회마을   DOI
4 I. B. Jung, E. Ko, C. Li and S. S. Park, Embry truncated complex moment problem, Linear Algebra Appl., 375(2003), 95-114.   DOI   ScienceOn
5 P. Halmos, Normal dilations and extensions of operators, Summa Bras. Math., 2(1950), 124-134.
6 C. Li and S. H. Lee, The quartic moment problem, J. Korean Math. Soc., 42(2005), 723-747.   과학기술학회마을   DOI
7 J. Stampfli, Which weighted shifts are subnormal? Pacific J. Math., 17(1966), 367-379.   DOI
8 J. Bram, Subnormal operators, Duke Math. J., 22(1955), 75-94.   DOI
9 R. Curto and L. Fialkow, Recursively generated weighted shifts and the subnormal completion problem, I, Integr. Equ. Oper. Theory, 17(1993), 202-246.   DOI
10 R. Curto and L. Fialkow, Recursively generated weighted shifts and the subnormal completion problem, II, Integr. Equ. Oper. Theory, 18(1994), 369-426.   DOI
11 R. Curto and L. Fialkow, Solution of the truncated complex moment problems for flat data, Memoirs Amer. Math. Soc., 568(1996).