S. Panja

activity

20222026

collaborators

7 papers

math.FA2026

Doubly commuting invariant and co-invariant subspaces

Sibaprasad Barik, Shubham Jain, Samir Panja

Given complex separable Hilbert spaces $H_{i}$ and bounded operators $T_{i}$ on $H_{i}$ , for $i = 1, \dots, n$ , we consider the tensor product space $\mathfrak{H}:=\math…

math.FA2026

Noncommutative commutant lifting, interpolation, and shift-invariant subspaces

Sibaprasad Barik, Samir Panja

We establish a Sarason-type commutant lifting theorem in the framework of noncommutative Drury-Arveson space and apply it to solve the noncommutative Nevanlinna-Pick interpolation…

math.FA2024

Liftings and invariant subspaces of Hankel operators

Sneha B, Neeru Bala, Samir Panja +1

We prove a Hankel-variant commutant lifting theorem. This also uncovers the complete structure of the Beurling-type reducing and invariant subspaces of Hankel operators. Kernel spa…

math.FA2024

de Branges-Rovnyak spaces which are complete Nevanlinna-Pick spaces

Hamidul Ahmed, B. Krishna Das, Samir Panja

We consider de Branges-Rovnyak spaces of a considerably large class of reproducing kernel Hilbert spaces and find a characterization for them to be complete Nevanlinna-Pick spaces.…

math.FA2023

Isometric dilation and Sarason's commutant lifting theorem in several variables

B. Krishna Das, Samir Panja

The article deals with isometric dilation and commutant lifting for a class of $n$ -tuples $(n \geq 3)$ of commuting contractions. We show that operator tuples in the class dilate t…

math.FA2022

Factorization of Toeplitz operators

Samir Panja

In this article, by considering $T = (T_{1}, \dots, T_{d})$ , an $d$ -tuple of commuting contractions on a Hilbert space $H$ , we study $T$ -Toeplitz operators which consists of bou…

math.FA2022

$\clw$-hypercontractions and their model

Monojit Bhattacharjee, B. Krishna Das, Ramlal Debnath +1

We revisit the study of $ω$ -hypercontractions corresponding to a single weight sequence $ω = {ω_{k}}_{k \geq 0}$ introduced by Olofsson in \cite{O} and find an analogue of Nagy-Foias c…