Journal of Mathematical Sciences

, Volume 172, Issue 2, pp 185–194 | Cite as

On Toeplitz operators with unimodular symbols: left invertibility and similarity to isometries


We consider Toeplitz operators with unimodular symbols on the Hardy space H 2 on the unit circle. Examples of inner functions θ andareal function w such that ||w|| = π/2 and the Toeplitz operator with symbol θe iw is not left-invertible are given. We also study Toeplitz operators that are similar to isometries. Bibliography: 28 titles.


Russia Unit Circle Real Function Hardy Space Toeplitz Operator 
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© Springer Science+Business Media, Inc. 2010

Authors and Affiliations

  1. 1.St. Petersburg Department of the Steklov Mathematical InstituteSt. PetersburgRussia

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