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arXiv · 1110.0577

Fredholm and invertibility theory for a special class of Toeplitz + Hankel operators

Estelle L. Basor·Torsten Ehrhardt
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Abstract

We develop a complete Fredholm and invertibility theory for Toeplitz+Hankel operators $T(a)+H(b)$ on the Hardy space $H^p$, $1<p<\infty$, with piecewise continuous functions $a,b$ defined on the unit circle which are subject to the condition $a(t)a(t^{-1})=b(t)b(t^{-1})$, $|t|=1$. In particular, in the case of Fredholmness, formulas for the defect numbers are established. The results are applied to several important examples.

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BibTeXRIS

Estelle L. Basor, Torsten Ehrhardt. 2011-10-04. Fredholm and invertibility theory for a special class of Toeplitz + Hankel operators. https://arxiv.org/abs/1110.0577

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