10 papers · 1 filter
On the shape of the numerical range of some tridiagonal matrices
Arobinda Ghosh, Riddhick Birbonshi, Sarita Ojha +1
In this paper, we study the elliptical shape of the numerical range of tridiagonal matrices of orders and with zero entries on the main diagonal, a positive constant valu…
Numerical range and invariant subspaces of weighted composition operators on the Hardy space of Dirichlet series
Sudeshna Lahiri, Sarita Ojha, Subhadip Halder +1
In this paper, we study various results on numerical range of weighted composition operators on Hardy space of Dirichlet series. Certain conditions are provided under which the num…
-Berezin sectorial operators with applications to -Berezin number inequalities and -Berezin ranges
Saikat Mahapatra, Subhadip Halder, Riddhick Birbonshi +2
In this paper, we introduce a new class of operators, called -Berezin sectorial operators, as an extension of the class of -sectorial operators. By presenting examples on the…
On the numerical radius of a class of weighted shift operators
Arobinda Ghosh, Riddhick Birbonshi, Sarita Ojha
In this paper, we derive some bounds on numerical radius of the weighted shift operator with weights where and . Furt…
Improved upper bounds for the Berezin numbers of operators on reproducing kernel Hilbert spaces
Riddhick Birbonshi, Sumon Ghosh, Fuad Kittaneh +2
In this article, several upper bounds for the Berezin numbers of bounded linear operators on reproducing kernel Hilbert spaces are obtained through the use of interpolation paths o…
Improved Bounds for numerical radius and -numerical radius in -algebras
Saikat Mahapatra, Arobinda Ghosh, Riddhick Birbonshi
In this article, we derive several significant upper bounds for the numerical radius and -numerical radius of an element in a -algebra by improving inequalities for posit…
On posinormality of weighted composition-differentiation operators on
Gour Hait, Sarita Ojha, Nirupam Ghosh +1
In this article, the posinormality and coposinormality of weighted composition-differentiation operators on Hardy space are investigated. It is observed that whil…
Iterated Aluthge transforms of some composition operators on weighted Bergman spaces
Sudeshna Lahiri, Sarita Ojha, Riddhick Birbonshi
In this paper, we compute the iterated Aluthge transforms of the composition operator on the weighted Bergman spaces , wh…
An introduction of Berezin sectorial operators and its application to Berezin number inequalities
Saikat Mahapatra, Sweta Mukherjee, Anirban Sen +2
We introduce a new class of operators, called Berezin sectorial operators, which generalizes classical sectorial operators. We provide examples on the Hardy-Hilbert space showing t…
A note on weighted composition operators on Dirichlet space
Subhadip Halder, Sweta Mukherjee, Riddhick Birbonshi
In this paper, we provide some sufficient conditions for the compactness of weighted composition operators on Dirichlet space. Furthermore, we characterize the numerical range of c…