P. Muthukumar

activity

20182021

collaborators

Showing math.FAShow all

5 papers · 1 filter

math.FA2021

Model spaces invariant under composition operators

P. Muthukumar, Jaydeb Sarkar

Given a holomorphic self-map $φ$ of $\D$ (the open unit disc in $C$ ), the composition operator $C_{φ} f = f \circ φ$ , $f \in H^2(\mathbb{\D})$, defines a bounded linear oper…

math.FA2020

Multiplication operators between discrete Hardy spaces on rooted trees

P. Muthukumar, P. Shankar

Muthukumar and Ponnusamy \cite{MP-Tp-spaces} studied the multiplication operators on $T_{p}$ spaces. In this article, we mainly consider multiplication operators between $\m…

math.FA2020

Beurling type invariant subspaces of composition operators

Snehasish Bose, P. Muthukumar, Jaydeb Sarkar

Let $D$ be the open unit disk in $C$ , let $H^{2}$ denote the Hardy space on $D$ and let $φ : D \to D$ be a holomorphic self map of…

math.FA2018

Estimate for norm of a composition operator on the Hardy-Dirichlet space

Perumal Muthukumar, Saminathan Ponnusamy, Hervé Queffélec

By using the Schur test, we give some upper and lower estimates on the norm of a composition operator on $H^{2}$ , the space of Dirichlet series with square summable coeffic…

math.FA2018

Weighted composition operators on the class of subordinate functions

Perumal Muthukumar, Saminathan Ponnusamy

In this article, we study the weighted composition operators preserving the class $P_{α}$ of analytic functions subordinate to $\frac{1 + α z}{1 - z}$ for $∣ α ∣ \leq 1, α \neq = - 1$ .…