Algebraic Graph Theory - Daniel Gromada

Monday, September 25, 2023 11:30 am - 11:30 am EDT (GMT -04:00)

Title: Quantum symmetries of Hadamard matrices

Speaker: Daniel Gromada
Affiliation: Czech Technical University in Prague
Location: Please contact Sabrina Lato for Zoom link

Abstract: The main purpose of this talk is to explain the idea behind the main results of a recent article arXiv:2210.02047 about quantum symmetries of Hadamard matrices. First, we recall the notion of quantum symmetries from the viewpoint of quantum groups as well as diagrammatic categories. On the example of a finite (quantum) space, we show, how the diagrammatic approach can be used to prove that all finite spaces (of size at least four) have quantum symmetries and all finite quantum spaces of a given size are mutually quantum isomorphic. The same technique is used to show analogous results for Hadamard matrices. Finally, we would like to list a couple of questions and research suggestions related to this topic.