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arXiv · 1804.08375

The Density Operators of Qubit Systems in the Multiparticle Spacetime Algebra

Chih-Wei Wang
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Abstract

We provide a method to write down the density operator for any pure state of multi-qubit systems in the multiparticle spacetime algebra (MSTA) introduced by Doran, Gull, and Lasenby. Using the MSTA formulation, we analyze several aspects of quantum mechanics in a geometrical way including the Bell inequality and the dynamics of two coupled qubits. Lastly, we provide a natural way to construct the local unitary invariants in the MSTA. Using these invariants, we analyze the space of the two-qubit and three-qubit pure states with local and non-local degrees of freedom separated.

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Chih-Wei Wang. 2018-04-23. The Density Operators of Qubit Systems in the Multiparticle Spacetime Algebra. https://arxiv.org/abs/1804.08375

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