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arXiv · 1407.2965

On the probabilistic nature of quantum mechanics and the notion of closed systems

Jérémy Faupin·Jürg Fröhlich·Baptiste Schubnel
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Abstract

The notion of "closed systems" in Quantum Mechanics is discussed. For this purpose, we study two models of a quantum-mechanical system $P$ spatially far separated from the "rest of the universe" $Q$. Under reasonable assumptions on the interaction between $P$ and $Q$, we show that the system $P$ behaves as a closed system if the initial state of $P \vee Q$ belongs to a large class of states, including ones exhibiting entanglement between $P$ and $Q$. We use our results to illustrate the non-deterministic nature of quantum mechanics. Studying a specific example, we show that assigning an initial state and a unitary time evolution to a quantum system is generally not sufficient to predict the results of a measurement with certainty.

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Jérémy Faupin, Jürg Fröhlich, Baptiste Schubnel. 2014-07-10. On the probabilistic nature of quantum mechanics and the notion of closed systems. https://arxiv.org/abs/1407.2965

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