Abstract
This paper makes a systematic study of kernels of Toeplitz operators on scalar and vector-valued H p spaces (for 1 < p < ∞). The property of near invariance of a kernel for the backward shift is analysed and shown to hold in increased generality. In the scalar case, and in some vectorial cases, the existence of a minimal kernel containing a given function is established, and a symbol for a corresponding Toeplitz operator is determined; thus, for rational symbols, its dimension can be easily calculated. It is shown that every Toeplitz kernel in H p is the minimal kernel for some function lying in it.
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This research was partially supported by FCT (Portugal) through program POCTI/FEDER and Project PEst-OE/EEI/LA0009/2013.
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Câmara, M.C., Partington, J.R. Near invariance and kernels of Toeplitz operators. JAMA 124, 235–260 (2014). https://doi.org/10.1007/s11854-014-0031-8
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DOI: https://doi.org/10.1007/s11854-014-0031-8