Disjointly non-singular operators: Extensions and local variations

The disjointly non-singular (DN-S) operators T∈L(E, Y) from a Banach lattice Eto a Banach space Yare those operators which are strictly singular in no closed subspace generated by a disjoint sequence of non-zero vectors. When Eis order continuous with a weak unit, Ecan be represented as a dense idea...

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Detalles Bibliográficos
Autores: González Ortiz, Manuel, Martinón, Antonio
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad de Cantabria (UC)
Repositorio:UCrea Repositorio Abierto de la Universidad de Cantabria
Idioma:inglés
OAI Identifier:oai:repositorio.unican.es:10902/32343
Acceso en línea:https://hdl.handle.net/10902/32343
Access Level:acceso abierto
Palabra clave:Disjointly non-singular operator
Disjointly strictly singular operator
Order continuous Banach lattice
Unbounded norm convergence
Descripción
Sumario:The disjointly non-singular (DN-S) operators T∈L(E, Y) from a Banach lattice Eto a Banach space Yare those operators which are strictly singular in no closed subspace generated by a disjoint sequence of non-zero vectors. When Eis order continuous with a weak unit, Ecan be represented as a dense ideal in some L1(μ) space, and we show that each T∈DN-S(E, Y) admits an extension T∈DN-S(L1(μ), PO), where POis certain Banach space, from which we derive that both Tand T∗∗are tauberian operators and that the operator Tco: E∗∗/E→Y∗∗/Y induced by T∗∗is an (into) isomorphism. Also, using a local variation of the notion of DN-S operator, we show that the ultrapowers of T∈DN-S(E, Y) are also DN-Soperators. Moreover, when Econtains no copies of c0and admits a weak unit, we show that T∈ DN-S(E, Y) implies T∗∗∈ DN-S(E∗∗, Y∗∗).