Hiding Ignorance Using High Dimensions
Phys. Rev. Lett. 124, 250401 – Published 22 June, 2020
DOI: https://doi.org/10.1103/PhysRevLett.124.250401
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 [T. Vidick and S. Wehner, Phys. Rev. Lett. 107, 030402 (2011).]. Experimentally verifying this counterintuitive fact requires controlling and measuring quantum systems of high dimension . We provide this experimental evidence using the transverse spatial modes of light, a powerful resource for testing high-dimensional quantum phenomena.
