[Sous-normalité de shifts pondérés à deux variables avec cœur diagonal]
Le problème du relèvement des opérateurs sous-normaux commutatifs (LPCS) consiste à rechercher des conditions nécessaires ou suffisantes pour que deux opérateurs sous-normaux sur lʼespace de Hilbert admettent des extensions normales commutatives. Étant donné un opérateur de décalage pondéré T à deux variables avec cœur diagonal, nous prouvons que le LPCS est résoluble pour T si et seulement si le LPCS est résoluble pour une certaine puissance . Nous le faisons en développant dʼabord les propriétés de base des cœurs diagonaux, puis en analysant la façon dont un cœur diagonal interagit avec le reste de lʼopérateur.
The Lifting Problem for Commuting Subnormals (LPCS) asks for necessary and sufficient conditions for a pair of subnormal operators on Hilbert space to admit commuting normal extensions. Given a 2-variable weighted shift T with diagonal core, we prove that LPCS is soluble for T if and only if LPCS is soluble for some power . We do this by first developing the basic properties of diagonal cores, and then analyzing how a diagonal core interacts with the rest of the 2-variable weighted shift.
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@article{CRMATH_2013__351_5-6_203_0,
author = {Curto, Ra\'ul Enrique and Lee, Sang Hoon and Yoon, Jasang},
title = {Subnormality of 2-variable weighted shifts with diagonal core},
journal = {Comptes Rendus. Math\'ematique},
pages = {203--207},
publisher = {Elsevier},
volume = {351},
number = {5-6},
year = {2013},
doi = {10.1016/j.crma.2013.03.002},
language = {en},
url = {http://www.numdam.org/articles/10.1016/j.crma.2013.03.002/}
}
TY - JOUR AU - Curto, Raúl Enrique AU - Lee, Sang Hoon AU - Yoon, Jasang TI - Subnormality of 2-variable weighted shifts with diagonal core JO - Comptes Rendus. Mathématique PY - 2013 SP - 203 EP - 207 VL - 351 IS - 5-6 PB - Elsevier UR - http://www.numdam.org/articles/10.1016/j.crma.2013.03.002/ DO - 10.1016/j.crma.2013.03.002 LA - en ID - CRMATH_2013__351_5-6_203_0 ER -
%0 Journal Article %A Curto, Raúl Enrique %A Lee, Sang Hoon %A Yoon, Jasang %T Subnormality of 2-variable weighted shifts with diagonal core %J Comptes Rendus. Mathématique %D 2013 %P 203-207 %V 351 %N 5-6 %I Elsevier %U http://www.numdam.org/articles/10.1016/j.crma.2013.03.002/ %R 10.1016/j.crma.2013.03.002 %G en %F CRMATH_2013__351_5-6_203_0
Curto, Raúl Enrique; Lee, Sang Hoon; Yoon, Jasang. Subnormality of 2-variable weighted shifts with diagonal core. Comptes Rendus. Mathématique, Tome 351 (2013) no. 5-6, pp. 203-207. doi : 10.1016/j.crma.2013.03.002. http://www.numdam.org/articles/10.1016/j.crma.2013.03.002/
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☆ The first named author was partially supported by NSF Grants DMS-0400741 and DMS-0801168. The second named author was partially supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009-0085279). The third named author was partially supported by a Faculty Research Council Grant at The University of Texas-Pan American.
