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arXiv · 1903.09487

Hiding Ignorance Using High Dimensions

M. J. Kewming·S. Shrapnel·A. G. White·J. Romero
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Abstract

The absence of information -- entirely or partly -- is called ignorance. Naturally, one might ask if some ignorance of a whole system will imply some ignorance of its parts. Our classical intuition tells us yes, however quantum theory tells us no: it is possible to encode information in a quantum system so that despite some ignorance of the whole, it is impossible to identify the unknown part arXiv:1011.6448. Experimentally verifying this counter-intuitive fact requires controlling and measuring quantum systems of high dimension $(d {>} 9)$. We provide this experimental evidence using the transverse spatial modes of light, a powerful resource for testing high dimensional quantum phenomenon.

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M. J. Kewming, S. Shrapnel, A. G. White, J. Romero. 2019-03-22. Hiding Ignorance Using High Dimensions. https://doi.org/10.1103/physrevlett.124.250401

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