Konstantinos Bampouras

collaborators

5 papers

math.CV2026

The norm of the backward shift on $H^{4}$ is $4 I ¨ $

Konstantinos Bampouras, AdriÃ¡n Llinares

We prove that the backward shift operator on $H^{4}$ has norm equal to $4 I ¨ $ , with $I ¨ = \frac{1 + 5}{2}$ . Furthermore, we characterize all extremal functions; they are…

math.FA2026

Recovering Product BMO from Schatten Hankel operators

Konstantinos Bampouras, Karl-Mikael Perfekt

We prove that if a small Hankel operator on the product Hardy space belongs to some Schatten class $S^{p}$ , $p < \infty$ , then it has a symbol in product BMO. In other words, the con…

math.FA2026

Nehari's Theorem and Hardy's inequality for Paley--Wiener spaces

Konstantinos Bampouras

Recently it was proven that for a convex subset of $R^{n}$ that has infinitely many extreme vectors, the Nehari theorem fails, that is, there exists a bounded Hankel opera…

math.FA2025

Besov spaces and Schatten class Hankel operators for Hardy and Paley--Wiener spaces in higher dimensions

Konstantinos Bampouras, Karl-Mikael Perfekt

We consider Schatten class membership of Hankel operators on Paley--Wiener spaces of convex $I^c ◯ \subset R^{n}$ , both for bounded and unbounded domains. In particular, the cla…

math.CV2025

Inner Functions, MÃ¶bius Distortion and Angular Derivatives

Konstantinos Bampouras, Artur Nicolau

We prove that an inner function has finite $L (p)$ -entropy if and only if its accumulated MÃ¶bius distortion is in $L^{p}$ , $0 < p < \infty$ . We also study the support of the p…