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arXiv · 2402.08060

Information gain and measurement disturbance for quantum agents

Arthur O. T. Pang·Noah Lupu-Gladstein·Y. Batuhan Yilmaz·C. Pria Dobney·Rui Jie Tang·Aharon Brodutch·Aephraim M. Steinberg
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Abstract

The traditional formalism of quantum measurement (hereafter ``TQM'') describes processes where some properties of quantum states are extracted and stored as classical information. While TQM is a natural and appropriate description of how humans interact with quantum systems, it is silent on the question of how a more general, quantum, agent would do so. How do we describe the observation of a system by an observer with the ability to store not only classical information but quantum states in its memory? In this paper, we extend the idea of measurement to a more general class of sensors for quantum agents which interact with a system in such a way that the agent's memory stores information (classical or quantum) about the system under study. For appropriate sensory interactions, the quantum agent may ``learn'' more about the system than would be possible under any set of classical measurements -- but as we show, this comes at the cost of additional measurement disturbance. We experimentally demonstrate such a system and characterize the tradeoffs by considering the channel capacity required to erase the effect of a measurement.

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Arthur O. T. Pang, Noah Lupu-Gladstein, Y. Batuhan Yilmaz, C. Pria Dobney, Rui Jie Tang, Aharon Brodutch, Aephraim M. Steinberg. 2024-02-12. Information gain and measurement disturbance for quantum agents. https://arxiv.org/abs/2402.08060

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