J. A. Virtanen

collaborators

4 papers

math.CV2026

Sharp exponential integrability of conjugate functions

David Norrbo, Jani Virtanen

We prove that if a real-valued function $f \in L^{1}$ on the complex unit circle has a gap of width at least $π$ in its essential range, then $exp (f)$ is not integrable, w…

math.FA2026

Carleson measures, tent embeddings, and Volterra-type integral operators on the unit ball

Xiaofen Lv, Xiaomin Tang, Jani A. Virtanen

In this paper, we establish a sharp comparison between Carleson-cube and Bergman-metric-ball conditions on the open unit ball $\B$ and combine it with a Berezin-type characterizati…

math.FA2024

The Hilbert matrix done right

A. Montes-Rodríguez, J. A. Virtanen

We give very simple proofs of the classical results of Magnus and Hill on the spectral properties of the Hilbert matrix $H = (\frac{1}{i + j + 1})_{i, j \geq 0}$ whi…

math.CV2024

Generalized Hilbert matrix operators acting on Bergman spaces

Carlo Bellavita, Vassilis Daskalogiannis, Santeri Miihkinen +3

In this article we study the generalized Hilbert matrix operator $Γ_{μ}$ acting on the Bergman spaces $A^{p}$ of the unit disc for $1 \leq p < \infty$ . In particular, we characterize the…