# Einstein, Incompleteness, and the Epistemic View of Quantum States

@article{Harrigan2007EinsteinIA, title={Einstein, Incompleteness, and the Epistemic View of Quantum States}, author={Nicholas M Harrigan and Robert W. Spekkens}, journal={Foundations of Physics}, year={2007}, volume={40}, pages={125-157} }

Does the quantum state represent reality or our knowledge of reality? In making this distinction precise, we are led to a novel classification of hidden variable models of quantum theory. We show that representatives of each class can be found among existing constructions for two-dimensional Hilbert spaces. Our approach also provides a fruitful new perspective on arguments for the nonlocality and incompleteness of quantum theory. Specifically, we show that for models wherein the quantum state…

## 366 Citations

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