English

Essentially isospectral transformations and their applications

Spectral Theory 2020-07-01 v2 Mathematical Physics Classical Analysis and ODEs Functional Analysis math.MP

Abstract

We define and study the properties of Darboux-type transformations between Sturm--Liouville problems with boundary conditions containing rational Herglotz--Nevanlinna functions of the eigenvalue parameter (including the Dirichlet boundary conditions). Using these transformations, we obtain various direct and inverse spectral results for these problems in a unified manner, such as asymptotics of eigenvalues and norming constants, oscillation of eigenfunctions, regularized trace formulas, and inverse uniqueness and existence theorems.

Keywords

Cite

@article{arxiv.1708.07497,
  title  = {Essentially isospectral transformations and their applications},
  author = {Namig J. Guliyev},
  journal= {arXiv preprint arXiv:1708.07497},
  year   = {2020}
}

Comments

27 pages, minor corrections, to appear in Annali di Matematica Pura ed Applicata

R2 v1 2026-06-22T21:22:56.398Z