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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Rényi Entropy, Signed Probabilities, and the Qubit
Adam Brandenburger1, Pierfrancesco La Mura2, Stuart Zoble3
1Stern School of Business, Tandon School of Engineering, NYU Shanghai, New York University, New York, NY 10012, USA.
Abstract:
The states of the qubit, the basic unit of quantum information, are 2 × 2 positive semi-definite Hermitian matrices with trace 1. We contribute to the program to axiomatize quantum mechanics by characterizing these states in terms of an entropic uncertainty principle formulated on an eight-point phase space. We do this by employing Rényi entropy (a generalization of Shannon entropy) suitably defined for the signed phase-space probability distributions that arise in representing quantum states.
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