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arXiv · 1910.06373

Spectral properties of the exponential distance matrix

Steve Butler·Elizabeth Coper·Aaron Li·Kate Lorenzen·Zoe Schopick
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Abstract

Given a graph $G$, the exponential distance matrix is defined entry-wise by letting the $(u,v)$-entry be $q^{\text{dist}(u,v)}$, where $\text{dist}(u,v)$ is the distance between the vertices $u$ and $v$ with the convention that if vertices are in different components, then $q^{\text{dist}(u,v)}=0$. In this paper, we will establish several properties of the characteristic polynomial (spectrum) for this matrix, give some families of graphs which are uniquely determined by their spectrum, and produce cospectral constructions.

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Steve Butler, Elizabeth Coper, Aaron Li, Kate Lorenzen, Zoe Schopick. 2019-10-14. Spectral properties of the exponential distance matrix. https://doi.org/10.2140/involve.2022.15.739

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