On a class of non-Hermitian matrices with positive definite Schur complements

Given a Hermitian matrices A∈C^n×n and D∈C^m×m, and k > 0, we characterize under which conditions there exists a matrix K∈C^n×m with ∥K∥ < k such that the non-Hermitian block-matrix [AK∗A−AKD] has a positive (semi-) definite Schur complement with respect to its submatrix A. Additionally, we sh...

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Detalles Bibliográficos
Autores: Berger, Thomas, Giribet, Juan Ignacio, Martinez Peria, Francisco Dardo, Trunk, Carsten Joachim
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/107578
Acceso en línea:http://hdl.handle.net/11336/107578
Access Level:acceso abierto
Palabra clave:FRAMES
KREIN SPACES
COMPLEMENTO DE SCHUR
OPERATOR DE CORTO-CIRCUITO
https://purl.org/becyt/ford/1.1
https://purl.org/becyt/ford/1
Descripción
Sumario:Given a Hermitian matrices A∈C^n×n and D∈C^m×m, and k > 0, we characterize under which conditions there exists a matrix K∈C^n×m with ∥K∥ < k such that the non-Hermitian block-matrix [AK∗A−AKD] has a positive (semi-) definite Schur complement with respect to its submatrix A. Additionally, we show that K can be chosen such that diagonalizability of the block-matrix is guaranteed and we compute its spectrum. Moreover, we show a connection to the recently developed frame theory for Krein spaces.