Johnson-Schwartzman Gap Labelling for Metric and Discrete Decorated Graphs

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Band, Ram, Sofer, Gilad
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866915927719673856
author Band, Ram
Sofer, Gilad
author_facet Band, Ram
Sofer, Gilad
contents We study Schrödinger operators on metric and discrete decorated graphs. The values taken by the integrated density of states (IDS) on spectral gaps are called gap labels. A natural question is which gap labels can occur. We answer this for graphs arising from uniquely ergodic one-dimensional dynamical systems by proving Johnson-Schwartzman gap-labelling theorems in both the metric and discrete settings. Our results extend Johnson-Schwartzman gap labelling beyond the standard one-dimensional setting. Unlike in one dimension, these graphs may contain cycles, which prevent the use of Sturm oscillation theory and require different spectral methods. We also analyze discontinuities of the IDS for certain graph families and show that not every admissible label corresponds to an open spectral gap. This reveals a mechanism of gap closing driven by graph geometry rather than by the underlying dynamics.
format Preprint
id arxiv_https___arxiv_org_abs_2604_08496
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Johnson-Schwartzman Gap Labelling for Metric and Discrete Decorated Graphs
Band, Ram
Sofer, Gilad
Spectral Theory
Mathematical Physics
Dynamical Systems
We study Schrödinger operators on metric and discrete decorated graphs. The values taken by the integrated density of states (IDS) on spectral gaps are called gap labels. A natural question is which gap labels can occur. We answer this for graphs arising from uniquely ergodic one-dimensional dynamical systems by proving Johnson-Schwartzman gap-labelling theorems in both the metric and discrete settings. Our results extend Johnson-Schwartzman gap labelling beyond the standard one-dimensional setting. Unlike in one dimension, these graphs may contain cycles, which prevent the use of Sturm oscillation theory and require different spectral methods. We also analyze discontinuities of the IDS for certain graph families and show that not every admissible label corresponds to an open spectral gap. This reveals a mechanism of gap closing driven by graph geometry rather than by the underlying dynamics.
title Johnson-Schwartzman Gap Labelling for Metric and Discrete Decorated Graphs
topic Spectral Theory
Mathematical Physics
Dynamical Systems
url https://arxiv.org/abs/2604.08496