Available in electronic format
Available in print format
Proceedings of the American Mathematical Society
Proceedings of the American Mathematical Society
ISSN 1088-6826 (e) ISSN 0002-9939 (p)
     

On the commutant and orbits of conjugation

Author(s): D. Drissi; M. Mbekhta
Journal: Proc. Amer. Math. Soc. 134 (2006), 1099-1106.
MSC (2000): Primary 47B10, 47B15
Posted: July 25, 2005
Retrieve article in: PDF

Abstract | References | Similar articles | Additional information

Abstract: In this note, we analyse the relationship between the commutant of a bounded linear operator $ A $ and the algebra of similarity $ B_A $ that was introduced in the late 70s as a characterization of nest algebras. Necessary and sufficient conditions are also obtained for an operator to commute with real scalar generalized operators in the sense of Colojoara-Foias in Banach spaces. In the second part, we analyse the relationship between the generalized inverse, the generalized commutant and the orbits of conjugation.


References:

1.
B. Aupetit and D. Drissi : Local spectrum & subharmonicity, Proc. Edinburgh Math. Soc., 39 (1996), 571-579. MR 1417698 (97j:47009)

2.
I. Colojoara and C. Foias : The Theory of Generalized Spectral Operators, Gordan and Breach, 1968. MR 0394282 (52:15085)

3.
J. A. Deddens and T. K. Wong : The commutant of analytic Toeplitz operators, Trans. Amer. Math. Soc., 184(1973), 261-273. MR 0324467 (48:2819)

4.
J. A. Deddens : Another description of nest algebras in Hilbert space operators, Lecture notes in Mathematics No. 693, (pp. 77-86), Springer-Verlag, Berlin, 1978. MR 0526534 (80f:47033)

5.
D. Drissi : Local spectrum and Kaplansky's theorem on algebraic operators. Colloq. Math., 75(1998), 159-165. MR 1490685 (98k:47005)

6.
D. Drissi and M. Mbekhta : Operators with bounded conjugation orbits, Proc. Amer. Math. Soc., 128(2000), 2687-2692. MR 1664345 (2000m:47024)

7.
D. Drissi and M. Mbekhta : Elements with generalized bounded conjugation orbits, Proc. Amer. Math. Soc., 129(2001), 2011-2016. MR 1825911 (2002e:47022)

8.
R. Harte and M. Mbekhta : Generalized inverses in $C^*$-algebras II, Studia Math. 106(1993), 129-138. MR 1240309 (94k:46113)

9.
T. Kato : Perturbation Theory for Linear Operators, Springer, New York, 1966. MR 0203473 (34:3324)

10.
G. Lumer and M. Rosenblum : Linear operator equations, Proc. Amer. Math. Soc. 10(1959), 32-41. MR 0104167 (21:2927)

11.
M. Mbekhta : Résolvant généralisé et théorie spectrale, J. of Operator Theory 21(1989), 69-105. MR 1002122 (91a:47004)

12.
M. Mbekhta : Conorme et inverse généralisé dans les $C^*-$algèbres, Canad. Math. Bull. 35 (1992), 515-522. MR 1191512 (94a:46075)

13.
M. Mbekhta and A. Ouahab : Opérateur s-régulier dans un espace de Banach et théorie spectrale, Acta Sci. Math. (Szeged) 59(1994), 525-543. MR 1317171 (96a:47018)

14.
M. Radjabalipour : Operators commuting with positive operators, Proc. Amer. Math. Soc. 77(1979), 107-110. MR 0539640 (81d:47013)

15.
P. G. Roth : Bounded orbits of conjugation, analytic theory, Indiana Univ. Math. J, 32 (1983), 491-509. MR 0703280 (85c:47039)

16.
J. G. Stampfli : On a question of Deddens in Hilbert space operators, Lecture Notes in Mathematics No. 693, (pp. 169-173), Springer-Verlag, Berlin, 1978. MR 0526546 (80f:47034)

17.
J. P. Williams : On a boundedness condition for operators with a singleton spectrum, Proc. Amer. Math. Soc. 78(1980), 30-32. MR 0548078 (81k:47008)


Similar Articles:

Retrieve articles in Proceedings of the American Mathematical Society with MSC (2000): 47B10, 47B15

Retrieve articles in all Journals with MSC (2000): 47B10, 47B15


Additional Information:

D. Drissi
Affiliation: Department of Mathematics, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait
Email: drissi@mcs.sci.kuniv.edu.kw

M. Mbekhta
Affiliation: UFR de Mathématiques, Université des Sciences et Technologie Lille, Villeneuve d'Asq, France
Email: Mostafa.Mbekhta@math.univ-lille1.fr

DOI: 10.1090/S0002-9939-05-08047-0
PII: S 0002-9939(05)08047-0
Keywords: Commutant, bounded orbit, spectrum, generalized inverse
Received by editor(s): October 14, 2004
Received by editor(s) in revised form: November 1, 2004
Posted: July 25, 2005
Communicated by: Joseph A. Ball
Copyright of article: Copyright 2005, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.


  AMS Website Logo Small Comments: webmaster@ams.org
© Copyright 2009, American Mathematical Society
Privacy Statement
Search the AMSPowered by Google