1 citations · 1 across the 5 of their papers we have counts for
7 papers
The operator-valued Schur-Agler class in infinitely many variables
Shubham Rastogi, Chaman Kumar Sahu
Motivated by a recent work of G. Knese [Canad. Math. Bull., 2026], we introduce the operator-valued Schur-Agler class in infinitely many variables, consisting of functions whose re…
Isometric dilations and Beurling quotient modules
B. Krishna Das, Shubham Rastogi
In \cite{Dan-Guo}, the authors provided a characterization of all sequences of doubly commuting pure contractions that have the sequence the sequence of the multipl…
On pure contractive semigroups
Shubham Rastogi, Vijaya Kumar U
We find the commutant of a pure contractive semigroup on a Hilbert space. We demonstrate that any tuple of doubly commuting pure contractive semigroups can be dilated to a tuple of…
Functions with image in a strip
Tirthankar Bhattacharyya, Anthony G. O'Farrell, Shubham Rastogi +1
We consider holomorphic functions on the unit disc whose images are contained in a strip of the complex plane. Under an additional condition, such functions are constants. We also…
Doubly commuting and dual doubly commuting semigroups of isometries
Tirthankar Bhattacharyya, Shubham Rastogi, Vijaya Kumar U
Structures of commuting semigroups of isometries under certain additional assumptions like double commutativity or dual double commutativity are found.
On factorization of the shift semigroup
Tirthankar Bhattacharyya, Shubham Rastogi, Kalyan B. Sinha +1
Let $\E$ be a finite dimensional Hilbert space. This note finds all factorizations of the right shift semigroup $§^\E=(S_t^\E)_{t\ge 0}$ on $L^2(\R_+,\E)$ into the product of c…
On the structure and the joint spectrum of a pair of commuting isometries
Tirthankar Bhattacharyya, Shubham Rastogi, Vijaya Kumar U
The study of a pair of commuting isometries is a classical theme. We shine new light on it by using the defect operator. In the cases when the defect operator is zero o…