3 papers
math.QA2026
Complex Hadamard Matrices - Quantum Symmetries, Equivalence and Non-Local Games
Michael Brannan, Daniel Gromada, Roberto Hernández Palomares +1
We consider quantum group generalizations of the action of monomial matrices on complex Hadamard matrices. This gives rise to various notions of quantum symmetries and quantum equi…
math.OA2025
A quantum Frucht's theorem and quantum automorphisms of quantum Cayley graphs
Michael Brannan, Daniel Gromada, Junichiro Matsuda +2
We establish a quantum version of Frucht's Theorem, proving that every finite quantum group is the quantum automorphism group of an undirected finite quantum graph. The constructio…
math.OA2025
Quantum expanders and property (T) discrete quantum groups
Michael Brannan, Eric Culf, Matthijs Vernooij
Families of expander graphs were first constructed by Margulis from discrete groups with property (T). Within the framework of quantum information theory, several authors have gene…