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Entanglement beyond subsystems

Lorenza Viola·Howard Barnum·Emanuel Knill·Gerardo Ortiz·Rolando Somma
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Abstract

We present a notion of generalized entanglement which goes beyond the conventional definition based on quantum subsystems. This is accomplished by directly defining entanglement as a property of quantum states relative to a distinguished set of observables singled out by Physics. While recovering standard entanglement as a special case, our notion allows for substantially broader generality and flexibility, being applicable, in particular, to situations where existing tools are not directly useful.

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Lorenza Viola, Howard Barnum, Emanuel Knill, Gerardo Ortiz, Rolando Somma. 2004-03-04. Entanglement beyond subsystems. https://arxiv.org/abs/quant-ph/0403044

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