Approximate Identities in Banach Algebras of Compact Operators
Canadian mathematical bulletin, Tome 36 (1993) no. 1, pp. 45-53

Voir la notice de l'article provenant de la source Cambridge University Press

Let X be a Banach space and let A be a uniformly closed algebra of compact operators on X, containing the finite rank operators. We set up a general framework to discuss the equivalence between Banach space approximation properties and the existence of right approximate identities in A. The appropriate properties require approximation in the dual X* by operators which are adjoints of operators on X. We show that the existence of a bounded right approximate identity implies that of a bounded left approximate identity. We give examples to show that these properties are not equivalent, however. Finally, we discuss the well known result that, if X* has a basis, then X has a shrinking basis. We make some attempts to generalize this to various bounded approximation properties.
DOI : 10.4153/CMB-1993-008-8
Mots-clés : 46B28, 46H20, 47D30, 47D50
Grønbæk, Niels; Willis, George A. Approximate Identities in Banach Algebras of Compact Operators. Canadian mathematical bulletin, Tome 36 (1993) no. 1, pp. 45-53. doi: 10.4153/CMB-1993-008-8
@article{10_4153_CMB_1993_008_8,
     author = {Gr{\o}nb{\ae}k, Niels and Willis, George A.},
     title = {Approximate {Identities} in {Banach} {Algebras} of {Compact} {Operators}},
     journal = {Canadian mathematical bulletin},
     pages = {45--53},
     year = {1993},
     volume = {36},
     number = {1},
     doi = {10.4153/CMB-1993-008-8},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1993-008-8/}
}
TY  - JOUR
AU  - Grønbæk, Niels
AU  - Willis, George A.
TI  - Approximate Identities in Banach Algebras of Compact Operators
JO  - Canadian mathematical bulletin
PY  - 1993
SP  - 45
EP  - 53
VL  - 36
IS  - 1
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1993-008-8/
DO  - 10.4153/CMB-1993-008-8
ID  - 10_4153_CMB_1993_008_8
ER  - 
%0 Journal Article
%A Grønbæk, Niels
%A Willis, George A.
%T Approximate Identities in Banach Algebras of Compact Operators
%J Canadian mathematical bulletin
%D 1993
%P 45-53
%V 36
%N 1
%U http://geodesic.mathdoc.fr/articles/10.4153/CMB-1993-008-8/
%R 10.4153/CMB-1993-008-8
%F 10_4153_CMB_1993_008_8

Berkson, E. and Porta, H., Representations of B(X), J. Funct. Anal. 3(1969) 1–34. Google Scholar

F. F Bonsall and Duncan, J., Complete Normed Algebras, Springer-Verlag, 1973, Berlin Heidelberg. Google Scholar

Diestel, J., Sequences and Series in Banach Spaces, Graduate Texts in Mathematics 92, Springer-Verlag, New York, 1984. Google Scholar

Diestel, J. and Uhl, J. J., Vector Measures, Math. Surveys 15, Amer. Math. Soc, 1977. Google Scholar

Dixon, P. G., Left approximate identities in algebras of compact operators on Banach spaces, Proc. Royal Soc. Edinburgh 104A(1989) 169–175. Google Scholar

Doran, R. S. and Wichmann, J., Approximate identities and factorization in Banach modules, Lecture Notes in Mathematics 768, Springer-Verlag, 1979, Berlin Heidelberg. Google Scholar

Dunford, N. and Schwartz, J. T., Linear Operators, Part 1, Interscience, New York, 1958. Google Scholar

Grothendieck, A., Résumé de la théorie métrique des produits tensoriels topologiques, Bol. Soc. Mat. Säo Paulo 8(1953) 1–70. Google Scholar

[G N. Gr0nbaek, Johnson, B. E. and Willis, G. A., Amenability of Banach algebras of compact operators, forthcoming paper. Google Scholar

B.Johnson, E., Cohomology in Banach algebras, Mem. Amer. Math. Soc. 127(1972). Google Scholar

Johnson, W. B., Rosenthal, H. P. and Zippin, M., On bases, finite-dimensional decompositions and weaker structures in Banach spaces, Israel J. Math. 9(1971) 488–506. Google Scholar

Lindenstrauss, J. and Tzafriri, L., Classical Banach Spaces 1, Springer-Verlag, 1977, Berlin Heidelberg. Google Scholar

Pietsch, A., Operator Ideals, North-Holland, Berlin, 1980. Google Scholar

Pisier, G., Factorization of Linear Operators and Geometry of Banach Spaces, Regional Conference Series in Mathematics 60, Amer. Math. Soc, Providence, Rhode Island, 1986. Google Scholar

Szankowski, A., B(H) does not have the approximation property, Acta. Math. 147(1981) 89–108. Google Scholar

Samuel, C., Bounded approximate identities in the algebra of compact operators on a Banach space, Proc. Amer. Math. Soc, to appear. Google Scholar

Willis, G. A., The compact approximation property does not imply the approximation property, forthcoming paper. Google Scholar

Cité par Sources :