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Quantum tensor product structures are observable-induced

Paolo Zanardi·Daniel Lidar·Seth Lloyd
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Abstract

It is argued that the partition of a quantum system into subsystems is dictated by the set of operationally accessible interactions and measurements. The emergence of a multi-partite tensor product structure of the state-space and the associated notion of quantum entanglement are then relative and observable-induced. We develop a general algebraic framework aimed to formalize this concept. We discuss several cases relevant to quantum information processing and decoherence control.

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Paolo Zanardi, Daniel Lidar, Seth Lloyd. 2003-08-07. Quantum tensor product structures are observable-induced. https://doi.org/10.1103/physrevlett.92.060402

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