Annals of Functional Analysis

Zero-dilation Indices of KMS Matrices

Hwa-Long Gau and Pei Yuan Wu

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The zero-dilation index $d(A)$ of an $n$-by-$n$ complex matrix $A$ is the maximum size of the zero matrix which can be dilated to $A$. In this paper, we determine the value of this index for a certain KMS matrix by using the Li--Sze characterization of higher-rank numerical ranges of a finite matrix.

Article information

Ann. Funct. Anal., Volume 5, Number 1 (2014), 30-35.

First available in Project Euclid: 5 February 2014

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Zentralblatt MATH identifier

Primary: 47A20: Dilations, extensions, compressions
Secondary: 15B05: Toeplitz, Cauchy, and related matrices 15A60: Norms of matrices, numerical range, applications of functional analysis to matrix theory [See also 65F35, 65J05]

Zero-dilation index KMS matrix higher-rank numerical range $S_n$-matrix $S_n^{-1}$-matrix


Gau, Hwa-Long; Wu, Pei Yuan. Zero-dilation Indices of KMS Matrices. Ann. Funct. Anal. 5 (2014), no. 1, 30--35. doi:10.15352/afa/1391614566.

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