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20172026
most citedColouring the normalized Laplacian

7 citations · 11 across the 8 of their papers we have counts for

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12 papers · 1 filter

math.CO2026

Total Conformal Rigidity in Graphs

Henrique Assumpção, Gabriel Coutinho, Chris Godsil

We introduce and study a generalization of conformal rigidity for graphs. A graph is -conformally rigid if the uniform edge weights simultaneously maximize the sum of the sm…

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.CO2023

No perfect state transfer in trees with more than 3 vertices

Gabriel Coutinho, Emanuel Juliano, Thomás Jung Spier

We prove that the only trees that admit perfect state transfer according to the adjacency matrix model are and . This answers a question first asked by Godsil in 2012 an…

math.CO2023

The spectrum of symmetric decorated paths

Gabriel Coutinho, Emanuel Juliano, Thomás Jung Spier

The main result of this paper states that in a rooted product of a path with rooted graphs which are disposed in a somewhat mirror-symmetric fashion, there are distinct eigenvalues…

math.CO2020

Fundamentals of fractional revival in graphs

Ada Chan, Gabriel Coutinho, Whitney Drazen +6

We develop a general spectral framework to analyze quantum fractional revival in quantum spin networks. In particular, we introduce generalizations of the notions of cospectral and…

math.CO20197 cited

Colouring the normalized Laplacian

Gabriel Coutinho, Rafael Grandsire, Célio Passos

We apply Cauchy's interlacing theorem to derive some eigenvalue bounds to the chromatic number using the normalized Laplacian matrix, including a combinatorial characterization of…