Haripada Sau

collaborators

5 papers

math.FA2023

Dilation and Model Theory for Pairs of Commuting Contractions

Joseph A. Ball, Haripada Sau

This manuscript is an effort to extend the Sz.-Nagy--Foias dilation and model theory for a single contraction to the case of commuting pair of contractions. Fundamental to the Sz.-…

math.FA2022

Functional Models for Commuting Hilbert-space Contractions

Joseph A. Ball, Haripada Sau

We develop a Sz.-Nagy--Foias-type functional model for a commutative contractive operator tuple $T = (T_{1}, \dots, T_{d})$ having $T = T_{1} \dots T_{d}$ equal to a completel…

math.FA2022

Dilation theory and functional models for tetrablock contractions

Joseph A. Ball, Haripada Sau

A classical result of Sz.-Nagy asserts that a Hilbert space contraction operator $T$ can be dilated to a unitary $\cU$. A more general multivariable setting for these ideas is the…

math.FA2022

Toeplitz operators and Hilbert modules on the symmetrized polydisc

Tirthankar Bhattacharyya, B. Krishna Das, Haripada Sau

When is the collection of $S$ -Toeplitz operators with respect to a tuple of commuting bounded operators $S = (S_{1}, S_{2}, \dots, S_{d - 1}, P)$ , which has the symmetri…

math.FA2022

Models for q-commutative tuples of isometries

Joseph A. Ball, Haripada Sau

A pair of Hilbert space linear operators $(V_{1}, V_{2})$ is said to be $q$ -commutative, for a unimodular complex number $q$ , if $V_{1} V_{2} = q V_{2} V_{1}$ . A concrete functional model for $q$ -co…