Graph States and the necessity of Euler Decomposition
Ross Duncan and Simon Perdrix
Abstract
Coecke and Duncan recently introduced a categorical formalisation of the interaction of complementary quantum observables. In this paper we use their diagrammatic language to study graph states, a computationally interesting class of quantum states. We give a graphical proof of the fixpoint property of graph states. We then introduce a new equation, for the Euler decomposition of the Hadamard gate, and demonstrate that Van den Nest's theorem–locally equivalent graphs represent the same entanglement–is equivalent to this new axiom. Finally we prove that the Euler decomposition equation is not derivable from the existing axioms.
Book Title
Computability in Europe: Mathematical Theory and Computational Practice (CiE'09)
Editor
Ambos−Spies‚ K. and Löwe‚ B. and Merkle‚ W.
Keywords
quantum computing; categorical quantum mechanics; graphical calculi; measurement−based quantum computing; entanglement
Note
Preprint available at http://arxiv.org/abs/0902.0500
Pages
167–177
Publisher
Springer
Series
Lecture Notes in Computer Science
Volume
5635
Year
2009