English

Visibility of quantum graph spectrum from the vertices

Spectral Theory 2018-01-19 v3 Mathematical Physics math.MP

Abstract

We investigate the relation between the eigenvalues of the Laplacian with Kirchhoff vertex conditions on a finite metric graph and a corresponding Titchmarsh-Weyl function (a parameter-dependent Neumann-to-Dirichlet map). We give a complete description of all real resonances, including multiplicities, in terms of the edge lengths and the connectivity of the graph, and apply it to characterize all eigenvalues which are visible for the Titchmarsh-Weyl function.

Keywords

Cite

@article{arxiv.1602.03394,
  title  = {Visibility of quantum graph spectrum from the vertices},
  author = {Christian Kühn and Jonathan Rohleder},
  journal= {arXiv preprint arXiv:1602.03394},
  year   = {2018}
}

Comments

Substantially revised version; accepted for publication in J. Phys. A: Math. Theor

R2 v1 2026-06-22T12:47:38.618Z