On the exact value of the norm of the Hilbert matrix operator on weighted Bergman spaces

Abstract

In this article, the open problem of finding the exact value of the norm of the Hilbert matrix operator on weighted Bergman spaces $A_{\alpha }^p$ is adressed. The norm was conjectured to be $\frac{\pi }{\sin \frac{(2+\alpha )\pi }{p}}$ by Karapetrović. We obtain a complete solution to the conjecture for $\alpha \ge 0$ and $2+\alpha +\sqrt{{\alpha }^2+\frac{7}{2}\alpha +3}\le p<2(2+\alpha )$ and a partial solution for $2+2\alpha <p<2+\alpha +\sqrt{{\alpha }^2+\frac{7}{2}\alpha +3}.$ Moreover, we also show that the conjecture is valid for small values of $\alpha$ when $2+2\alpha <p\le 3+2\alpha .$ Finally, the case $\alpha =1$ is considered.

21 pages