4 papers
von Neumann Inequality for a class of Doubly Contractive Weighted Shifts
Soumyadip Dey, Rajeev Gupta, Surjit Kumar
In this article, we investigate the ball version of von Neumann inequality for the class of doubly contractive -tuple of weighted shift. We show that if the weighted shift is ba…
Function Theory on Tetrablock: Realization, Interpolation, Extension and Toeplitz Corona Theorem
Shubham Jain, Surjit Kumar, Milan Kumar Mal +1
We introduce a Schur-Agler type class associated with the tetrablock and establish a realization theorem for this class. Furthermore, we provide a tetrablock analog of the interpol…
Brown-Halmos type characterization for the tetrablock
Shubham Jain, Surjit Kumar, Milan Kumar Mal +1
In this note, we obtain a Brown-Halmos type characterization for Toeplitz operators on the Hardy space associated with the tetrablock. As an application, we show that the zero oper…
Cartan Isometries and Toeplitz Operators on Cartan domains
Surjit Kumar, Milan Kumar Mal, Paramita Pramanick
We provide a description of the Shilov boundary of the classical Cartan domain in terms of Jordan triple determinant. As a consequence, we obtained an intrinsic characterization of…