/manager/Index ${session.getAttribute("locale")} 5 On quotient digraphs and voltage digraphs /manager/Repository/uon:30377 α . We prove that all the eigenvalues of ⌈ (including multiplicities) are, in addition, eigenvalues of ⌈α. This study is carried out by introducing several reduced matrix representations of ⌈α. As an example of our techniques, we study some basic properties of the Alegre digraph and its base.]]> Wed 11 Apr 2018 14:19:34 AEST ]]> From expanded digraphs to lifts of voltage digraphs and line digraphs /manager/Repository/uon:30378 Wed 11 Apr 2018 12:26:06 AEST ]]> An algebraic approach to lifts of digraphs /manager/Repository/uon:36785 α of a voltage digraph, which has arcs weighted by the elements of a group. As a main result, when the involved group is Abelian, we completely determine the spectrum of Γα. As some examples of our technique, we study some basic properties of the Alegre digraph, and completely characterize the spectrum of a new family of digraphs, which contains the generalized Petersen graphs, and the Hoffman-Singleton graph.]]> Mon 06 Jul 2020 09:53:43 AEST ]]>