Spectral Theory and Descriptive Combinatorics for Non-Regular Borel pmp Graphs
Abstract
We continue the systematic study initiated in arXiv:2602.05185 of the relationship between the spectral theory and descriptive combinatorics of bounded-degree Borel pmp graphs, particularly in the non-regular setting. We first adapt a classical result of Nikiforov to give a new spectral lower bound on the approximate measurable chromatic number. For certain non-regular graphs, this bound improves on the approximate measurable version of Hoffman's classical bound established in arXiv:2602.05185. Next, we strengthen a characterization in arXiv:2602.05185 of approximate measurable bipartiteness in terms of the spectrum of the adjacency operator by generalizing to the case of non-regular graphs. Finally, we introduce the measurable domination number and adapt several classical results of Lu, Liu, and Tian to give a bound on the spectral gap of the Laplacian operator in terms of the measurable domination number.
Related
- Extremal spectral gap of regular graphs with bounded vertex connectivity
- The Spectral Theory of Threshold Graphs: A Survey
- Interval endomorphism algebras of posets: Reedy structure, combinatorics, and homological theory
- Edge universality of random regular graphs of growing degrees
- Internal partitions of $5$-regular and $8$-regular graphs
BibTeX
@misc{higgins2026spectral,
title = {{Spectral Theory and Descriptive Combinatorics for Non-Regular Borel pmp Graphs}},
author = {Cecelia Higgins and Pieter Spaas and Sofia Torelli},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.13551},
eprint = {2610.13551},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.13551},
}
RIS
TY - UNPB
TI - Spectral Theory and Descriptive Combinatorics for Non-Regular Borel pmp Graphs
AU - Cecelia Higgins
AU - Pieter Spaas
AU - Sofia Torelli
PY - 2026
DA - 2026/10/09
PB - arXiv
DO - 10.48550/arxiv.2610.13551
UR - https://arxiv.org/abs/2610.13551
AB - We continue the systematic study initiated in arXiv:2602.05185 of the relationship between the spectral theory and descriptive combinatorics of bounded-degree Borel pmp graphs, particularly in the non-regular setting. We first adapt a classical result of Nikiforov to give a new spectral lower bound on the approximate measurable chromatic number. For certain non-regular graphs, this bound improves on the approximate measurable version of Hoffman's classical bound established in arXiv:2602.05185. Next, we strengthen a characterization in arXiv:2602.05185 of approximate measurable bipartiteness in terms of the spectrum of the adjacency operator by generalizing to the case of non-regular graphs. Finally, we introduce the measurable domination number and adapt several classical results of Lu, Liu, and Tian to give a bound on the spectral gap of the Laplacian operator in terms of the measurable domination number.
ER -