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A de Finetti representation for finite symmetric quantum states

Robert Koenig·Renato Renner
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Abstract

Consider a symmetric quantum state on an n-fold product space, that is, the state is invariant under permutations of the n subsystems. We show that, conditioned on the outcomes of an informationally complete measurement applied to a number of subsystems, the state in the remaining subsystems is close to having product form. This immediately generalizes the so-called de Finetti representation to the case of finite symmetric quantum states.

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Robert Koenig, Renato Renner. 2004-10-27. A de Finetti representation for finite symmetric quantum states. https://doi.org/10.1063/1.2146188

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