Cet article présente la solution d'un problème posé par B.Sz.-Nagy sur l'extension du théorème de dilatation des commutants au cas des opérateurs sous-jacents qui ne commutent pas. Le théorème principal établit des dilatations aux normes minimales de certains commutateurs. La démonstration est constructive.
This paper presents the solution to a problem proposed by B.Sz.-Nagy about extending the commutant lifting theorem to the case when the underlying operators do not intertwine. The main theorem establishes minimal norm liftings of certain commutators. The proof is constructive.
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@article{CRMATH_2002__335_5_431_0, author = {Foias, Ciprian and Frazho, Arthur E. and Kaashoek, Marinus A.}, title = {Contractive liftings and the commutator}, journal = {Comptes Rendus. Math\'ematique}, pages = {431--436}, publisher = {Elsevier}, volume = {335}, number = {5}, year = {2002}, doi = {10.1016/S1631-073X(02)02508-6}, language = {en}, url = {http://www.numdam.org/articles/10.1016/S1631-073X(02)02508-6/} }
TY - JOUR AU - Foias, Ciprian AU - Frazho, Arthur E. AU - Kaashoek, Marinus A. TI - Contractive liftings and the commutator JO - Comptes Rendus. Mathématique PY - 2002 SP - 431 EP - 436 VL - 335 IS - 5 PB - Elsevier UR - http://www.numdam.org/articles/10.1016/S1631-073X(02)02508-6/ DO - 10.1016/S1631-073X(02)02508-6 LA - en ID - CRMATH_2002__335_5_431_0 ER -
%0 Journal Article %A Foias, Ciprian %A Frazho, Arthur E. %A Kaashoek, Marinus A. %T Contractive liftings and the commutator %J Comptes Rendus. Mathématique %D 2002 %P 431-436 %V 335 %N 5 %I Elsevier %U http://www.numdam.org/articles/10.1016/S1631-073X(02)02508-6/ %R 10.1016/S1631-073X(02)02508-6 %G en %F CRMATH_2002__335_5_431_0
Foias, Ciprian; Frazho, Arthur E.; Kaashoek, Marinus A. Contractive liftings and the commutator. Comptes Rendus. Mathématique, Tome 335 (2002) no. 5, pp. 431-436. doi : 10.1016/S1631-073X(02)02508-6. http://www.numdam.org/articles/10.1016/S1631-073X(02)02508-6/
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