English

Asymptotic spectral properties of the Hilbert $L$-matrix

Spectral Theory 2022-08-03 v2 Classical Analysis and ODEs

Abstract

We study asymptotic spectral properties of the generalized Hilbert LL-matrix Ln(ν)=(1max(i,j)+ν)i,j=0n1, L_{n}(\nu)=\left(\frac{1}{\max(i,j)+\nu}\right)_{i,j=0}^{n-1}, for large order nn. First, for general ν0,1,2,\nu\neq0,-1,-2,\dots, we deduce the asymptotic distribution of eigenvalues of Ln(ν)L_{n}(\nu) outside the origin. Second, for ν>0\nu>0, asymptotic formulas for small eigenvalues of Ln(ν)L_{n}(\nu) are derived. Third, in the classical case ν=1\nu=1, we also prove asymptotic formulas for large eigenvalues of LnLn(1)L_{n}\equiv L_{n}(1). I particular, we obtain an asymptotic expansion of Ln\|L_{n}\| improving Wilf's formula for the best constant in truncated Hardy's inequality.

Keywords

Cite

@article{arxiv.2202.04116,
  title  = {Asymptotic spectral properties of the Hilbert $L$-matrix},
  author = {František Štampach},
  journal= {arXiv preprint arXiv:2202.04116},
  year   = {2022}
}

Comments

18 pages, dedicated to the memory of Harold Widom, accepted for publication in SIAM J. Matrix Anal. Appl