Finite fields and Ramanujan graphs
A connected \(k\)-regular graph is called a Ramanujan graph if the modulus of any eigenvalue (of its adjacency matrix), different from \(\pm k\), does not exceed \(2\sqrt{k-1}\). The author gives a new method to construct Ramanujan graphs, and he constructs two new families of Ramanujan graphs.
scientific article; zbMATH DE number 1042498
scientific article