English

Spectral gaps of simplicial complexes without large missing faces

Combinatorics 2019-10-16 v1

Abstract

Let XX be a simplicial complex on nn vertices without missing faces of dimension larger than dd. Let LjL_{j} denote the jj-Laplacian acting on real jj-cochains of XX and let μj(X)\mu_{j}(X) denote its minimal eigenvalue. We study the connection between the spectral gaps μk(X)\mu_{k}(X) for kdk\geq d and μd1(X)\mu_{d-1}(X). In particular, we establish the following vanishing result: If μd1(X)>(1(k+1d)1)n\mu_{d-1}(X)>(1-\binom{k+1}{d}^{-1})n, then H~j(X;R)=0\tilde{H}^{j}(X;\mathbb{R})=0 for all d1jkd-1\leq j \leq k. As an application we prove a fractional extension of a Hall-type theorem of Holmsen, Mart\'inez-Sandoval and Montejano for general position sets in matroids.

Keywords

Cite

@article{arxiv.1706.00358,
  title  = {Spectral gaps of simplicial complexes without large missing faces},
  author = {Alan Lew},
  journal= {arXiv preprint arXiv:1706.00358},
  year   = {2019}
}
R2 v1 2026-06-22T20:06:30.366Z