Quantum Sabidussi's Theorem
Abstract
Sabidussi's theorem [Duke Math. J. 28, 1961] gives necessary and sufficient conditions under which the automorphism group of a lexicographic product of two graphs is a wreath product of the respective automorphism groups. We prove a quantum version of Sabidussi's theorem for finite graphs, with the automorphism groups replaced by quantum automorphism groups and the wreath product replaced by the free wreath product of quantum groups. This extends the result of Chassaniol [J. Algebra 456, 2016], who proved it for regular graphs. Moreover, we apply our result to lexicographic products of quantum vertex transitive graphs, determining their quantum automorphism groups even when Sabidussi's conditions do not apply.
Cite
@article{arxiv.2402.12344,
title = {Quantum Sabidussi's Theorem},
author = {Arnbjörg Soffía Árnadóttir and Josse van Dobben de Bruyn and Prem Nigam Kar and David E. Roberson and Peter Zeman},
journal= {arXiv preprint arXiv:2402.12344},
year = {2024}
}
Comments
21 pages, 2 figures. Minor changes, mostly improvements to the exposition