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arXiv · 2604.04536

Signless Laplacian spectral radius of simplicial complexes without $r$-dimensional wheels

Huan-Zhi Zhang·Yi-Zheng Fan
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Abstract

An $r$-dimensional wheel is defined as the join of an $(r-2)$-simplex and a cycle. In this paper, we study the maximum signless Laplacian spectral radius of $n$-vertex $r$-dimensional pure simplicial complexes that contain no $r$-dimensional wheels. For sufficiently large $n$, we determine the extremal complexes that attain this maximum. Our result generalizes the corresponding extremal results of signless Laplacian on graphs and provides a spectral anlogue of a theorem of S\'os, Erd\H{o}s and Brown on the maximum number of facets of simplicial complexes in the case $r=2$.

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Huan-Zhi Zhang, Yi-Zheng Fan. 2026-04-06. Signless Laplacian spectral radius of simplicial complexes without $r$-dimensional wheels. https://arxiv.org/abs/2604.04536

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