3 papers
math.FA2026
On -partial isometries: spectra, weighted shifts, and similarity
Mohamed Amine Aouichaoui, MichaÅ BuchaÅa, Stephan Ramon Garcia
The aim of this paper is to study -partial isometries on Hilbert spaces, a natural extension of partial isometries and -isometries. We establish structural and spectral resul…
math.FA2025
Every expansive -concave operator has -isometric dilation
MichaÅ BuchaÅa
The aim of this paper is to obtain -isometric dilation of expansive -concave operator on Hilbert space. The obtained dilation is shown to be minimal. The matrix represent…
math.FA2025
m-isometric weighted shifts with operator weights
MichaÅ BuchaÅa
The aim of this paper is to study -isometric weighted shifts with operator weights (both unilateral and bilateral). We obtain a characterization of such shifts by polynomials…