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The Six Algebraic Islands

Classification

Systematic enumeration of algebraic number rings reveals exactly six "islands" — families of rays in \(\mathbb{C}^3\) that produce KS-uncolorable pools with distinct graph types. Each island is defined by a number ring whose generators satisfy a norm-\(\leq 2\) cancellation identity.

Note: "six islands" refers to six distinct graph families, not six rings. Some rings produce isomorphic orthogonality graphs — for instance, \(\mathbb{Z}[\sqrt{-2}]\), Gaussian integers \(\mathbb{Z}[i]\), and Peres' \(\mathbb{Z}[\sqrt{2}]\) all produce the same "Peres graph." These are counted as one island (the Peres island) with multiple algebraic realizations.

# Island Ring Min KS Cancellation Identity Pool Size
1 Integer (CK-31) \(\mathbb{Z}\) 31 \(1+1=2\) 49
2 Peres \(\mathbb{Z}[\sqrt{2}]\) 33 \((\sqrt{2})^2 = 2\) 49
3 Eisenstein \(\mathbb{Z}[\omega]\) 33 \(1+\omega+\omega^2 = 0\) 57
4 \(\mathbb{Z}[\sqrt{-2}]\) \(\mathbb{Z}[\sqrt{-2}]\) 33 $ \sqrt{-2}
5 Heegner-7 \(\mathbb{Z}[(1+\sqrt{-7})/2]\) 43 \(\alpha \cdot \bar{\alpha} = 2\) 145
6 Golden \(\mathbb{Z}[\varphi]\) 52 \(\varphi^2 = \varphi + 1\) 205

Islands 2, 4, and Gaussian (\(\mathbb{Z}[i]\)) are graph-isomorphic — they share the same orthogonality graph (the "Peres graph") despite using different algebraic coordinates. This means there are five distinct graph types among the six algebraic islands.


The Norm-2 Boundary

The central organizing principle is the generator norm: for a ring element \(\alpha\) to participate in KS-producing orthogonalities, it must satisfy a cancellation identity with "norm" \(\leq 2\) (where norm refers to \(|\alpha|^2\) or the algebraic norm \(\alpha \bar{\alpha}\)).

What works (norm \(\leq 2\)): - \(1 + 1 = 2\) (integers) - \((\sqrt{2})^2 = 2\) (Peres) - \(1 + \omega + \omega^2 = 0\) (Eisenstein, norm 1) - \(\alpha \bar{\alpha} = 2\) for \(\alpha = (1+\sqrt{-7})/2\) (Heegner-7) - \(\varphi^2 = \varphi + 1\) (Golden)

What doesn't work (norm \(\geq 3\)): - \(\{0, \pm 1, \pm 3\}\) — no KS set (lacks \(1+1=2\)) - \(\{0, \pm 1, \pm 4\}\) — no KS set - Plastic ratio, tribonacci, silver ratio, supersilver — all colorable - Heegner numbers \(d = 11, 19, 43, 67, 163\) — all colorable (norm too large)


Sub-31 Optimality

Strong computational evidence that CK-31 is the minimum KS set in dimension 3:

OCUS Proof (Integer Pool) — Proved

The OCUS (Optimal Constrained Unsatisfiable Subset) algorithm exhaustively proved that no \(\leq 30\)-vector KS subset exists in the 49-ray integer pool \(\{0, \pm 1, \pm 2\}\). Completed in 272 iterations (0.1 seconds).

Six Independent Strategies — Computational evidence

Strategy Method Result
1. SAT minimization MUS + greedy + swap on all 6 pools All pools: min = known minimum
2. Cross-pool mixing All 15 pairwise + full 477-ray union Cross-pool rays never help
3. Larger alphabets 30 expanded alphabets tested Every alphabet with \(\{0,\pm 1,\pm 2\}\) → 31
4. Numerical optimization SA, perturbation, completion Zero triads from random rays
5. CK-31 criticality Exhaustive k=1..8, sampled k=9..12 8-critical (all subsets colorable)
6. Triad density bounds Random rays in \(\mathbb{R}^3\) and \(\mathbb{C}^3\) Zero orthogonal pairs in random samples

Key finding: Every alphabet containing \(\{0, \pm 1, \pm 2\}\) converges to CK-31 as its minimum. Alphabets lacking \(\pm 2\) are either not KS-uncolorable or stay at \(\geq 33\).


Graph Universality of CK-31 — Proved (VF2-verified)

All 31-vertex KS sets found by any method — integer alphabet, rational coordinates, mixed-field constructions, \(A_4\) and \(S_4\) group orbits — share the same orthogonality graph (verified by VF2 isomorphism, both graph and hypergraph).

This universality means the CK-31 graph is the unique minimal graph supporting KS-uncolorability in 3D with integer-type coordinates. Negative controls confirm: rings like \(\mathbb{Z}[\sqrt{3}]\), \(\mathbb{Z}[\sqrt{-5}]\) produce pools with many bases but all are KS-colorable.


MUS Landscape — Computational result

From 5000 MUS (Minimal Unsatisfiable Subset) trials on the 49-ray integer pool, exactly 6 distinct minimal 31-sets exist:

  • 13 core rays (\(\|v\|^2 \leq 3\)) appear in all 6 sets — the \(\{0, \pm 1\}\) skeleton
  • 12 rays never used — all with \(\|v\|^2 = 9\) (highest norm)
  • Norm stratification: \(\|v\|^2 = 1,2,3 \to\) core (100%); \(\|v\|^2 = 5 \to\) 83%; \(\|v\|^2 = 6 \to\) 67%; \(\|v\|^2 = 9 \to\) 0%
  • No swap connectivity — minimum Hamming distance 5 between any two sets
  • CK-31 is one of the 6 (rediscovered as set 5)

Merge Saturation — Computational result; conjecture for general case

All six minimal KS sets exhibit 100% merge preservation: merging any pair of non-orthogonal vertices preserves KS-uncolorability.

Island Min Non-orth pairs Preserved Rate
CK-31 31 394 394 100%
Peres-33 33 456 456 100%
Eisenstein-33 33 450 450 100%
\(\mathbb{Z}[\sqrt{-2}]\)-33 33 456 456 100%
Heegner-7 43 796 796 100%
Golden-52 52 1204 1204 100%

Total: 3,756 merges, all preserving KS-uncolorability. This motivates the merge-saturation conjecture (open): every minimal KS set in \(\mathbb{R}^3\)/\(\mathbb{C}^3\) is merge-saturated.


Rigidity Classification — Proved (Jacobian null space)

Island Vectors Pairs Null dim Sym dim Deformation Status
CK-31 31 71 39 39 0 Rigid
Eisenstein-33 33 78 41 41 0 Rigid
Peres-33 33 72 42 41 1 Flex
\(\mathbb{Z}[\sqrt{-2}]\)-33 33 72 42 41 1 Flex
Heegner-7 43 107 51 51 0 Rigid
Golden-52 52 124 60 60 0 Rigid

The Peres and \(\mathbb{Z}[\sqrt{-2}]\) flex is infinitesimal only — blocked at second order. Both are finitely rigid. The flex belongs to their shared graph (72 pairs vs Eisenstein's 78), not to the choice of algebraic ring.


BPQS / Bell Connections

Each KS set defines a bipartite perfect quantum strategy (BPQS), connecting the KS theorem to Bell nonlocality. Status varies per island — see the "Status" column:

| Island | \(|S_A| \times |S_B|\) | Product | Status | |--------|---------------------|---------|--------| | Eisenstein-33 | \(5 \times 9\) | 45 | Exact | | Peres-33 | \(7 \times 9\) | 63 | Exact | | CK-31 | \(8 \times 9\) | \(\leq 72\) | Best found | | \(\mathbb{Z}[\sqrt{-2}]\)-33 | \(7 \times 9\) | 63 | Exact (= Peres) | | Heegner-7 | \(9 \times 12\) | \(\leq 108\) | Best found | | Golden-52 | \(12 \times 13\) | \(\leq 156\) | Best found |

The Eisenstein-33 set achieves the smallest known BPQS (45) among all 3D KS sets.


The 6|n Cyclotomic Theorem — Proved (algebraic proof)

Theorem: The cyclotomic ray pool \(S_n\) (rays with coordinates in \(\mathbb{Q}(\zeta_n)\)) is KS-uncolorable if and only if \(6 | n\).

This is proved by complete algebraic argument (no computational evidence needed):

  • Sufficiency: When \(6|n\), the Eisenstein 33-set embeds (since \(\omega = \zeta_3 \in \mathbb{Q}(\zeta_n)\) when \(3|n\))
  • Case 1 (\(3 \nmid n\), \(2 \nmid n\)): Only the axis triad exists; trivially colorable
  • Case 2 (\(3 \nmid n\), \(2 | n\)): Each non-axis ray has exactly one orthogonal partner; explicit coloring constructed
  • Case 3 (\(3 | n\), \(2 \nmid n\)): Projective collapse reduces 6 permutations to 2 rays; each ray participates in exactly one triad; colorable by triad decomposition

References

  • M. Kernaghan, "The Algebraic Landscape of Kochen-Specker Sets in Dimension Three" (2026)
  • M. Kernaghan, "New KS Sets from Algebraic Number Fields with Enhanced Contextual Advantage" (2026)
  • M. Kernaghan, "Graph Universality of CK-31 and the Norm-2 Boundary" (2026)
  • M. Kernaghan, "Computational Evidence for the Optimality of CK-31" (2026)
  • M. Kernaghan, "Kochen-Specker Uncolorability in Cyclotomic Fields Requires Exactly 6|n" (2026)
  • A. Cabello, "Simplest Kochen-Specker Set," Phys. Rev. Lett. (2025), arXiv:2508.07335
  • A. Cabello, "Simplest Bipartite Perfect Quantum Strategies," Phys. Rev. Lett. 134, 010201 (2024)
  • S. Trandafir and A. Cabello, rigidity of KS sets (2024)
  • Liu et al., "Equivalence between FNS, FN, AVN, PT," Phys. Rev. Research 6, L042035 (2024)
  • F. Li, A. Bright, and V. Ganesh, SAT-based KS search, IJCAI 2024, arXiv:2306.13319