Sergei Treil

collaborators

3 papers

math.SP2026

Inverse spectral problems for positive Hankel operators

Alexander Pushnitski, Sergei Treil

A Hankel operator $I^$ in $L^{2} (R_{+})$ is an integral operator with the integral kernel of the form $h (t + s)$ , where $h$ is known as the kernel function. It is known that $Î…

math.RA2025

The spectral map for weighted Cauchy matrices is an involution

Alexander Pushnitski, Sergei Treil

Let $N$ be a natural number. We consider weighted Cauchy matrices of the form \[ \mathcal{C}_{a,A}=\left\{\frac{\sqrt{A_j A_k}}{a_k+a_j}\right\}_{j,k=1}^N, \] where $A_{1}, \dots, A_{N}$ …

math.SP2025

Unbounded integral Hankel operators

Alexander Pushnitski, Sergei Treil

For a wide class of unbounded integral Hankel operators on the positive half-line, we prove essential self-adjointness on the set of smooth compactly supported functions.