On Invertible m-isometrical Extension of an m-isometry

Results in Mathematics - Tập 77 - Trang 1-21 - 2022
T. Bermúdez1, A. Martinón2, V. Müller3, H. Zaway4,5
1Departamento de Análisis Matemático, Universidad de La Laguna and Instituto de Matemáticas y Aplicaciones (IMAULL), San Cristóbal de La Laguna, Spain
2Departamento de Análisis Matemático, Universidad de La Laguna, San Cristóbal de La Laguna, Spain
3Mathematical Institute, Czech Academy of Sciences, Prague 1, Czech Republic
4Department of Mathematics, Faculty of Sciences, University of Gabes, Gabes, Tunisia
5Department of Mathematics and Statistics, University of King Faisal, Al Ahsa, Saudi Arabia

Tóm tắt

We give necessary and sufficient conditions on an m-isometry to have an invertible m-isometrical extension. As particular cases, we give a useful characterization for a general m-isometrical unilateral weighted shift and for $$\ell $$ -Jordan isometries. In particular, every $$\ell $$ -Jordan isometry operator has an invertible $$(2\ell -1)$$ -isometrical extension.

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