S. Daptari

collaborators

3 papers

math.FA2025

On relationship among three types of Birkhoff-James orthogonality

Soumitra Daptari, Koki Igarashi, Jumpei Nakamura +1

In this paper, we study three types of Birkhoff-James orthogonality in Hilbert $C^{*}$ -modules, that is, the strong, quasi-strong, and original Birkhoff-James orthogonality. In gener…

math.FA2025

A study on state spaces in classical Banach spaces

Soumitra Daptari, Saurabh Dwivedi

Let $X$ be a real or complex Banach space. Let $S (X)$ denote the unit sphere of $X$ . For $x \in S (X)$ , let $S_{x} = {x^{*} \in S (X^{*}) : x^{*} (x) = 1}$ . A lot of Banach space geometry can be…

math.FA2025

A study of weak $^{*}$ -weak points of continuity in the unit ball of dual spaces

S. Daptari, V. Montesinos, T. S. S. R. K. Rao

We study classes of Banach spaces where the points of weak $^{*}$ -weak continuity for the identity mapping on the dual unit ball form a weak $^{*}$ -dense and weak $^{*}$ - $G_{I^} ´$ set. We also…

On relationship among three types of Birkhoff-James orthogonality

A study on state spaces in classical Banach spaces

A study of weak∗-weak points of continuity in the unit ball of dual spaces

A study of weak $^{*}$ -weak points of continuity in the unit ball of dual spaces