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arXiv · 2008.10617

Do qubits dream of entangled sheep? Quantum measurement without classical output

Noah Lupu-Gladstein·Aharon Brodutch·Hugo Ferretti·Weng-Kian Tham·Arthur Ou Teen Pang·Kent Bonsma-Fisher·Aephraim M. Steinberg
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Abstract

Quantum mechanics is usually formulated with an implicit assumption that agents who can observe and interact with the world are external to it and have a classical memory. However, there is no accepted way to define the quantum-classical cut and no a priori reason to rule out fully quantum agents with coherent quantum memories. In this work, we introduce an entirely quantum notion of measurement, called a sensation, to account for quantum agents that experience the world through quantum sensors. Sensations eschew probabilities and instead describe a deterministic flow of quantum information. We quantify the information gain and disturbance of a sensation using concepts from quantum information theory and find that sensations always disturb at least as much as they inform. Viewing measurements as sensations could lead to a new understanding of quantum theory in general and to new results in the context of quantum networks.

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Noah Lupu-Gladstein, Aharon Brodutch, Hugo Ferretti, Weng-Kian Tham, Arthur Ou Teen Pang, Kent Bonsma-Fisher, Aephraim M. Steinberg. 2020-08-24. Do qubits dream of entangled sheep? Quantum measurement without classical output. https://doi.org/10.1088/1367-2630/ad48ad

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