Block Toeplitz Operators with Frequency- Modulated Semi-almost Periodic Symbols
نویسنده
چکیده
This paper is concerned with the influence of frequency modulation on the semiFredholm properties of Toeplitz operators with oscillating matrix symbols. The main results give conditions on an orientation-preserving homeomorphism α of the real line that ensure the following: if b belongs to a certain class of oscillating matrix functions (periodic, almost periodic, or semi-almost periodic matrix functions) and the Toeplitz operator generated by the matrix function b(x) is semi-Fredholm, then the Toeplitz operator with the matrix symbol b(α(x)) is also semi-Fredholm.
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