Proceedings of the London Mathematical Society Advance Access originally published online on November 4, 2008
Proceedings of the London Mathematical Society 2009 98(3):652-678; doi:10.1112/plms/pdn048
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© 2008 London Mathematical Society
Topological stable rank of nest algebras
Pure Mathematics Department
University of Waterloo
Waterloo
Ontario
Canada N2L 3G1
Mathematics Department
Jilin University
Changchun 130012
PR China
jiyq@jlu.edu.cn
Received 13 March 2008. Revision received 5 September 2008.
We establish a general result about extending a right invertible row over a Banach algebra to an invertible matrix. This is applied to the computation of right topological stable rank of a split exact sequence. We also introduce a quantitative measure of stable rank. These results are applied to compute the right (left) topological stable rank for all nest algebras. This value is either 2 or infinity, and rtsr (
(
)) = 2 occurs only when
is of ordinal type less than
2 and the dimensions of the atoms grows sufficiently quickly. We introduce general results on partial matrix algebras over a Banach algebra. This is used to obtain an inequality akin to Rieffel's formula for matrix algebras over a Banach algebra. This is used to give further insight into the nest case.
2000 Mathematics Subject Classification 47A35, 47L75, 19B10.
The first author was partially supported by an NSERC grant. The second author was partially supported by RFDP(20050183002), NCET and the China Scholarship Council.