2020/04/03 by Florian Lehner, Lehner, Florian, Gabriel Verret +1
Computer Science · Engineering · #Advanced Graph Theory Research #Combinatorics (math.CO) #Complexity and Algorithms in Graphs #FOS: Mathematics #graph theory and CDMA systems
paper · pdf · doi:10.48550/arxiv.2004.01327
openalex publication_date 2020/04/03 · openalex created_date 2020/04/10 · openalex updated_date 2026/07/28
Recently, Huang gave a very elegant proof of the Sensitivity Conjecture by proving that hypercube graphs have the following property: every induced subgraph on a set of more than half its vertices has maximum degree at least √(d), where d is the valency of the hypercube. This was generalised by Alon and Zheng who proved that every Cayley graph on an elementary abelian 2-group has the same property. Very recently, Potechin and Tsang proved an analogous results for Cayley graphs on abelian groups. They also conjectured that all Cayley graphs have the analogous property. We disprove this conjecture by constructing various counterexamples, including an infinite family of Cayley graphs of unbounded valency which admit an induced subgraph of maximum valency 1 on a set of more than half its vertices.