Geometry of unitary orbits of pinching operators
Let I be a symmetrically-normed ideal of the space of bounded operators acting on a Hilbert space H. Let {pi}1w(1≤w≤∞) be a family of mutually orthogonal projections on H. The pinching operator associated with the former family of projections is given by P:I→I,P(x)=∑i=1wpixpi. Let UI denote the Bana...
Autores principales: | , |
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Formato: | Articulo |
Lenguaje: | Inglés |
Publicado: |
2013
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Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/85541 |
Aporte de: |
id |
I19-R120-10915-85541 |
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record_format |
dspace |
institution |
Universidad Nacional de La Plata |
institution_str |
I-19 |
repository_str |
R-120 |
collection |
SEDICI (UNLP) |
language |
Inglés |
topic |
Matemática Covering space Left representation Pinching operator Submanifold Symmetrically-normed ideal |
spellingShingle |
Matemática Covering space Left representation Pinching operator Submanifold Symmetrically-normed ideal Chiumiento, Eduardo Hernán Di Iorio y Lucero, M. E. Geometry of unitary orbits of pinching operators |
topic_facet |
Matemática Covering space Left representation Pinching operator Submanifold Symmetrically-normed ideal |
description |
Let I be a symmetrically-normed ideal of the space of bounded operators acting on a Hilbert space H. Let {pi}1w(1≤w≤∞) be a family of mutually orthogonal projections on H. The pinching operator associated with the former family of projections is given by P:I→I,P(x)=∑i=1wpixpi. Let UI denote the Banach-Lie group of the unitary operators whose difference with the identity belongs to I. We study geometric properties of the orbit UI(P)={LuPLu*:u∈UI}, where Lu is the left representation of UI on the algebra B(I) of bounded operators acting on I. The results include necessary and sufficient conditions for UI(P) to be a submanifold of B(I). Special features arise in the case of the ideal K of compact operators. In general, UK(P) turns out to be a non complemented submanifold of B(K). We find a necessary and sufficient condition for UK(P) to have complemented tangent spaces in B(K). We also show that UI(P) is a covering space of another orbit of pinching operators. |
format |
Articulo Articulo |
author |
Chiumiento, Eduardo Hernán Di Iorio y Lucero, M. E. |
author_facet |
Chiumiento, Eduardo Hernán Di Iorio y Lucero, M. E. |
author_sort |
Chiumiento, Eduardo Hernán |
title |
Geometry of unitary orbits of pinching operators |
title_short |
Geometry of unitary orbits of pinching operators |
title_full |
Geometry of unitary orbits of pinching operators |
title_fullStr |
Geometry of unitary orbits of pinching operators |
title_full_unstemmed |
Geometry of unitary orbits of pinching operators |
title_sort |
geometry of unitary orbits of pinching operators |
publishDate |
2013 |
url |
http://sedici.unlp.edu.ar/handle/10915/85541 |
work_keys_str_mv |
AT chiumientoeduardohernan geometryofunitaryorbitsofpinchingoperators AT diiorioylucerome geometryofunitaryorbitsofpinchingoperators |
bdutipo_str |
Repositorios |
_version_ |
1764820489491972098 |