Best approximation by diagonal compact operators

We study the existence and characterization properties of compact Hermitian operators C on a Hilbert space H such that the norm of C is less or equal to that of C + D , for all the real and compact diagonals D in a fixed base of H (in the operator norm). We also exhibit a positive trace class operat...

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Detalles Bibliográficos
Autores: Bottazzi, Tamara Paula, Varela, Alejandro
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/3338
Acceso en línea:http://hdl.handle.net/11336/3338
Access Level:acceso abierto
Palabra clave:Minimal Compact Operator
Diagonal Operator
Quotient Operator Norm
Best Approximation
https://purl.org/becyt/ford/1.1
https://purl.org/becyt/ford/1
Descripción
Sumario:We study the existence and characterization properties of compact Hermitian operators C on a Hilbert space H such that the norm of C is less or equal to that of C + D , for all the real and compact diagonals D in a fixed base of H (in the operator norm). We also exhibit a positive trace class operator that fails to attain the minimum in a compact diagonal.