Amitay Kamber, Tali Kaufman. Combinatorics via closed orbits: number theoretic Ramanujan graphs are not unique neighbor expanders. In Stefano Leonardi, Anupam Gupta 0001, editors, STOC '22: 54th Annual ACM SIGACT Symposium on Theory of Computing, Rome, Italy, June 20 - 24, 2022. pages 426-435, ACM, 2022. [doi]
Abstract is missing.