# A de Finetti representation for finite symmetric quantum states

@article{Koenig2004ADF, title={A de Finetti representation for finite symmetric quantum states}, author={Robert Koenig and Renato Renner}, journal={Journal of Mathematical Physics}, year={2004}, volume={46}, pages={122108} }

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.

## 117 Citations

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