4 papers
Tightness of a MaxCut Lower Bound via Vector Chromatic Number
Emanuel Juliano
Recently, Balla, Janzer, and Sudakov showed a lower bound on the MaxCut in terms of the vector chromatic number, recovering known results on the MaxCut of -free graphs. In this…
Computing fixed point free automorphisms of graphs
Aida Abiad, Gabriel Coutinho, Emanuel Juliano +2
In 1981, Lubiw proved that the fixed point free automorphism problem (FPFAut) is NP-complete: given a graph G, determine whether there exists an automorphism that maps no vertex of…
The edge-isoperimetric number of graphs and their powers: approaches from spectral graph theory, optimization and finite geometry
Aida Abiad, Nils van de Berg, Emanuel Juliano +4
We obtain several sharp spectral bounds, approximations, and exact values for the isoperimetric number and related edge-expansion parameters of graphs. Our results focus on graph p…
A graph energy conjecture through the lenses of semidefinite programming
Aida Abiad, Gabriel Coutinho, Emanuel Juliano +1
Let be a graph on vertices with independence number . Let be the energy of a graph, defined as the sum of the absolute values of the adjacency eigen…