7 papers
Noncommutative -differentiability and trace formulae
Arup Chattopadhyay, Clément Coine, Saikat Giri +1
Let be a semifinite von Neumann algebra equipped with a normal faithful semifinite trace , and let denote the associated noncommutative -sp…
On modules of the Hardy space of Hartogs triangle
Arup Chattopadhyay, Saikat Giri, Shubham Jain
In this paper, we investigate the structure of doubly commuting submodules and quotient modules of the Hardy space over the Hartogs triangle. We establish a comp…
Trace formulas for -perturbations and extension of Koplienko-Neidhardt trace formulas
Arup Chattopadhyay, Clément Coine, Saikat Giri +1
In this paper, we extend the class of admissible functions for the trace formula of the second order in the self-adjoint, unitary, and contraction cases for a perturbation in the H…
Higher order -differentiability: The unitary case
Arup Chattopadhyay, Clément Coine, Saikat Giri +1
Consider the set of unitary operators on a complex separable Hilbert space $\hilh$, denoted as $\mathcal{U}(\hilh)$. Consider . We establish that a function defined…
Lipschitz Estimates and an application to trace formulae
Tirthankar Bhattacharyya, Arup Chattopadhyay, Saikat Giri +1
In this note, we provide an elementary proof for the expression of in the form of a double operator integral for every Lipschitz function on the unit circle $\cir$…
Estimates and Higher-Order Spectral Shift Measures in Several Variables
Arup Chattopadhyay, Saikat Giri, Chandan Pradhan
In recent years, higher-order trace formulas of operator functions have attracted considerable attention to a large part of the perturbation theory community. In this direction, we…
Trace formulas in higher dimensions
Arup Chattopadhyay, Saikat Giri, Chandan Pradhan +1
The paper establishes the Krein and Koplienko trace formulas for multivariable operator functions on symmetrically normed ideals of bounded operators. Results are proved for self-a…