Abstract
We obtain a Halmos–Richter-type wandering subspace theorem for covariant representations of \(C^*\)-correspondences. Further the notion of Cauchy dual and a version of Shimorin’s Wold-type decomposition for covariant representations of \(C^*\)-correspondences is explored and as an application a wandering subspace theorem for doubly commuting covariant representations is derived. Using this wandering subspace theorem generating wandering subspaces are characterized for covariant representations of product systems in terms of the doubly commutativity condition.
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Acknowledgements
Shankar V. is grateful to The LNM Institute of Information Technology for providing research facility and warm hospitality during a visit in March 2019. Shankar V. is supported by CSIR Fellowship (File No: 09/115(0782)/2017-EMR-I).
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Trivedi, H., Veerabathiran, S. Generating Wandering Subspaces for Doubly Commuting Covariant Representations. Integr. Equ. Oper. Theory 91, 35 (2019). https://doi.org/10.1007/s00020-019-2533-3
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DOI: https://doi.org/10.1007/s00020-019-2533-3
Keywords
- Hilbert \(C^*\)-modules
- Isometry
- Covariant representations
- Product systems
- Doubly commuting
- Shimorin property
- Wandering subspaces
- Wold decomposition
- Fock space