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  • Open Access

Faithful real embedding of a three-dimensional complex Kochen-Specker configuration

Andrei Khrennikov1,* and Karl Svozil2,†

  • 1Institutionen för Matematik, Fakulteten för Teknik, Linnaeus University, SE-351 95 Växjö, Sweden
  • 2Institute for Theoretical Physics, TU Wien, Wiedner Hauptstrasse 8-10/136, 1040 Vienna, Austria

Phys. Rev. A 113, 032206 – Published 10 March, 2026

DOI: https://doi.org/10.1103/2pf4-bq7p

Abstract

We describe a phase-adjusted realification procedure that embeds any finite set of rays in C3 into R6. By assigning an appropriate phase to each ray before applying the standard coordinatewise map, we can arrange that two rays are orthogonal in C3 if and only if their images are orthogonal in R6, so the construction yields a faithful orthogonal representation of the original complex configuration. As a concrete example, we consider the 165 projectively distinct rays used in a C3 Kochen-Specker configuration obtained from mutually unbiased bases, list these 165 rays explicitly in C3, and give for each of them its image in R6 under the canonical realification map. We also note that, because the original three -element contexts are no longer maximal in R6, the embedded configuration admits two-valued states even though its realization with maximal contexts in C3 is Kochen-Specker uncolorable.

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