6 papers · 1 filter
Commutant lifting, interpolation, and perturbations on the polydisc
Deepak K. D., Jaydeb Sarkar
The fundamental theorem on commutant lifting due to Sarason does not carry over to the setting of the polydisc. This paper presents two classifications of commutant lifting in seve…
Isometric pairs with compact and normal cross-commutator
Sandipan De, Jaydeb Sarkar, P Shankar +1
We represent and classify pairs of commuting isometries acting on Hilbert spaces that satisfy the condition \[ [V_1^*, V_2] = \text{compact and normal}, \] where $[V_1…
Contractive representations of odometer semigroup
Anindya Ghatak, Narayan Rakshit, Jaydeb Sarkar +1
Given a natural number , the odometer semigroup , also known as the adding machine or the Baumslag-Solitar monoid with two generators, is a well-known object in grou…
Inner and characteristic functions in polydiscs
Ramlal Debnath, Deepak K. Pradhan, Jaydeb Sarkar
Characteristic functions of linear operators are analytic functions that serve as complete unitary invariants. Such functions, as long as they are built in a natural and canonical…
A Bishop-Phelps-Bollobás theorem for bounded analytic functions
Neeru Bala, Kousik Dhara, Jaydeb Sarkar +1
Let denote the Banach algebra of all bounded analytic functions on the open unit disc and denote by the Banach space of all bounded linear operat…
Analytic primes, -ideals, and -sets in
Deepak K. D, Jaydeb Sarkar, Sreejith Siju
We investigate the structure of -sets, -ideals, and a newly introduced notion of analytic primes in , where denotes the Banach al…