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Picturing Qubits in Phase Space

William K. Wootters
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Abstract

Focusing particularly on one-qubit and two-qubit systems, I explain how the quantum state of a system of n qubits can be expressed as a real function--a generalized Wigner function--on a discrete 2^n x 2^n phase space. The phase space is based on the finite field having 2^n elements, and its geometric structure leads naturally to the construction of a complete set of 2^n+1 mutually conjugate bases.

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William K. Wootters. 2003-08-09. Picturing Qubits in Phase Space. https://arxiv.org/abs/quant-ph/0306135

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