Linear discrete operators on the disk algebra

Authors:
Ivan V. Ivanov and Boris Shekhtman

Journal:
Proc. Amer. Math. Soc. **129** (2001), 1987-1993

MSC (2000):
Primary 46-XX

Published electronically:
December 13, 2000

MathSciNet review:
1825906

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Abstract | References | Similar Articles | Additional Information

Let be the disk algebra. In this paper we address the following question: Under what conditions on the points do there exist operators such that

and , , for every ? Here the convergence is understood in the sense of norm in . Our first result shows that if satisfy Carleson condition, then there exists a function such that , . This is a non-trivial generalization of results of Somorjai (1980) and Partington (1997). It also provides a partial converse to a result of Totik (1984). The second result of this paper shows that if are required to be projections, then for any choice of the operators do not converge to the identity operator. This theorem generalizes the famous theorem of Faber and implies that the disk algebra does not have an interpolating basis.

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Additional Information

**Ivan V. Ivanov**

Affiliation:
Department of Mathematics, Texas A & M University, College Station, Texas 77843

Email:
ivanov@math.tamu.edu

**Boris Shekhtman**

Affiliation:
Department of Mathematics, University of South Florida, Tampa, Florida 33620

Email:
boris@2chuma.cas.usf.edu

DOI:
http://dx.doi.org/10.1090/S0002-9939-00-05774-9

Received by editor(s):
November 30, 1998

Received by editor(s) in revised form:
October 15, 1999

Published electronically:
December 13, 2000

Additional Notes:
The results in this paper are part of the Ph.D. thesis of the first author.

Communicated by:
Dale Alspach

Article copyright:
© Copyright 2000
American Mathematical Society