Abstract
We obtain a factorization of the characteristic function of a contractive two-step iterated lifting in terms of the characteristic functions of constituent liftings of the iterated lifting and the Julia–Halmos matrix. We also give an expression for the characteristic function of the minimal part of a contractive two-step iterated lifting as a restriction of the product of the characteristic functions of constituent liftings of the iterated lifting.
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Acknowledgements
The first author was supported by the Department of Mathematics, IIT Bombay, India. The second author was supported by SERB MATRICS Grant Number MTR/2018/000343.
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Communicated by Tirthankar Bhattacharyya.
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Bala, N., Dey, S. & Reshmi, M.N. Factorizations of Characteristic Functions of Iterated Liftings. Complex Anal. Oper. Theory 17, 79 (2023). https://doi.org/10.1007/s11785-023-01370-8
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DOI: https://doi.org/10.1007/s11785-023-01370-8
Keywords
- Row contractions
- Contractive lifting
- Fock space
- Characteristic functions
- Multi-analytic operators
- Completely non-coisometric