50 citations · 57 across the 10 of their papers we have counts for
10 papers
A matrix representation of graphs and its spectrum as a graph invariant
David Emms, Edwin R. Hancock, Simone Severini +1
We use the line digraph construction to associate an orthogonal matrix with each graph. From this orthogonal matrix, we derive two further matrices. The spectrum of each of these t…
Entangling Power of Permutations
Lieven Clarisse, Sibasish Ghosh, Simone Severini +1
The notion of entangling power of unitary matrices was introduced by Zanardi, Zalka and Faoro [PRA, 62, 030301]. We study the entangling power of permutations, given in terms of a…
Mediated Digraphs and Quantum Nonlocality
Gregory Gutin, Nick S. Jones, Arash Rafiey +2
A digraph D=(V,A) is mediated if, for each pair x,y of distinct vertices of D, either xy belongs to A or yx belongs to A or there is a vertex z such that both xz,yz belong to A. Fo…
Hamilton Cycles in Digraphs of Unitary Matrices
Gregory Gutin, Arash Rafiey, Simone Severini +1
A set is called an {\em -set} ({\em -set}, respectively) if has at least two vertices and, for every , there exists such that…
Quadrangularity in Tournaments
J. Richard Lundgren, Simone Severini, Dustin J. Stewart
The pattern of a matrix M is a (0,1)-matrix which replaces all non-zero entries of M with a 1. There are several contexts in which studying the patterns of orthogonal matrices can…
Quantum Algorithms and Covering Spaces
Tobias J. Osborne, Simone Severini
In this paper we isolate the combinatorial property responsible (at least in part) for the computational speedups recently observed in some quantum walk algorithms. We find that co…