Ammann-Beenker (Octagonal)

Eightfold diffraction symmetry, Bragg peak contrast, cardinal-diagonal anisotropy
quasicrystaldim 2D with 8-fold2 metrics

What It Measures

Does the signal have eightfold diffraction symmetry — the signature of Ammann-Beenker quasicrystals?

Uses the same spectral self-similarity machinery as Penrose but tests for the silver ratio (1 + sqrt(2) = 2.414...) instead of the golden ratio. Ammann-Beenker tilings fill the plane with squares and 45-degree rhombi, creating 8-fold rotational symmetry that is forbidden in periodic crystals.

Metrics

eightfold_symmetry

Spectral self-similarity under silver-ratio scaling. Unlike Penrose, no source in the atlas achieves a perfect score. DNA Centromere leads at 0.285: repetitive genomic elements may produce weak silver-ratio correlations. LIGO Hanford (0.216) and Logistic Chaos (0.210) score modestly — these are likely coincidental partial matches rather than genuine octagonal order. The absence of strong detections is itself informative: no 1D source in the atlas has true eightfold quasicrystalline structure.

long_range_order

Autocorrelation self-similarity at silver-ratio lags. Scores are near zero across the entire atlas. Kuramoto (0.005) is the highest — its coupled oscillator dynamics produce weak ratio-scaled correlations. This confirms that silver-ratio long-range order is genuinely rare in 1D signals.

Atlas Rankings

eightfold_symmetry
SourceDomainValue
DNA Centromerebio0.2848
LIGO Hanfordastro0.2163
Logistic Chaoschaos0.2103
···
Rossler Attractorchaos0.0000
fBm (Antipersistent)noise0.0000
Constant 0xFFnoise0.0000
long_range_order
SourceDomainValue
Kuramoto Oscillatorsexotic0.0046
Chirikov Standard Mapchaos0.0006
Solar Wind IMFastro0.0000
···
Logistic Chaoschaos0.0000
Henon Mapchaos0.0000
Tent Mapchaos0.0000

When It Lights Up

Ammann-Beenker serves as a null control within the quasicrystal lens. Its consistently near-zero scores across the atlas validate that the detection machinery is specific: the same algorithm that produces 1.0 for golden-ratio sources on Penrose produces near-zero for silver-ratio sources on Ammann-Beenker, confirming that the Penrose detections are ratio-specific rather than artifacts of the spectral analysis method. If a source ever does score highly on eightfold_symmetry, it would genuinely deserve investigation as a silver-ratio quasicrystal.

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