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20202026
most citedSums of squares of eigenvalues and the vector chromatic number

3 citations · 4 across the 8 of their papers we have counts for

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6 papers · 1 filter

math.CO2026

Resolution of a problem of Mohar on non-positive inertia

Clive Elphick, Hitesh Kumar, Shivaramakrishna Pragada +1

For a graph of order , its positive, negative and non-positive inertia is the number of positive, negative and non-positive eigenvalues of its adjacency matrix , respe…

math.CO2025

Eigenvalues of Universal Covers and the Matching Polynomial

Thomás Jung Spier

In this work, we prove that the universal and maximal abelian covers of a finite multi-graph have the same eigenvalues. This result strengthens a recent theorem of Li, Magee, Sabri…

math.CO2025

Efficient reconstruction of the characteristic polynomial

Thomás Jung Spier

The polynomial reconstruction problem, introduced by Cvetković in 1973, asks whether the characteristic polynomial of a graph with at least vertices can be reconstruc…

math.CO2024

Conic programming to understand sums of squares of eigenvalues of graphs

Gabriel Coutinho, Thomás Jung Spier, Shengtong Zhang

In this paper we prove a conjecture by Wocjan, Elphick and Anekstein (2018) which upper bounds the sum of the squares of the positive (or negative) eigenvalues of the adjacency mat…

math.CO20233 cited

Sums of squares of eigenvalues and the vector chromatic number

Gabriel Coutinho, Thomás Jung Spier

In this short paper we prove that the sum of the squares of negative (or positive) eigenvalues of the adjacency matrix of a graph is lower bounded by the sum of the degrees divided…

math.CO20201 cited

On Graph Continued Fractions and the Heilmann-Lieb Theorem

Thomás Jung Spier

Inspired by Viennot's observation that matching polynomials are numerators of branched continued fractions we present a proof of the Heilmann-Lieb Theorem.