Septagonal (Danzer)

Sevenfold diffraction symmetry, Danzer tiling order
quasicrystaldim 2D with 7-fold5 metrics

What It Measures

Does the signal have sevenfold diffraction symmetry — the rarest rotational order in known quasicrystals?

Tests spectral self-similarity at the septagonal ratio rho = 1 + 2*cos(2*pi/7) ~ 2.247, the largest root of x^3 - 2x^2 - x + 1 = 0. The v2 evolution discovered a triple-conjugate ensemble approach: the three roots of the minimal polynomial (rho, its conjugate, and its reciprocal) provide independent spectral probes. Sevenfold symmetry is crystallographically forbidden and extremely rare even among quasicrystals.

Metrics

cubic_coherence

Combined coherence across all three roots of the septagonal minimal polynomial. Tests the algebraic identity x^3 = 2x^2 + x - 1 in spectral space. Evolved via ShinkaEvolve.

z_primary

Spectral self-coherence at the primary septagonal ratio rho ~ 2.247.

z_conjugate

Spectral self-coherence at the conjugate root ~ 1.802. Independent probe of the same algebraic structure.

z_reciprocal

Spectral self-coherence at the reciprocal root ~ 0.445. Completes the triple-conjugate ensemble.

ratio_symmetry

Generic spectral self-similarity under septagonal-ratio scaling. Shared QC spectral machinery.

Atlas Rankings

cubic_coherence
SourceDomainValue
Bearing Outerbearing0.2479
LIGO Livingstonastro0.2183
Solar Wind IMFastro0.2018
···
Circle Map Quasiperiodicchaos-0.2729
Phyllotaxisbio-0.2558
Fibonacci Wordexotic-0.2270
ratio_symmetry
SourceDomainValue
Tohoku Aftershock Intervalsgeophysics0.3376
DNA Centromerebio0.3237
LIGO Hanfordastro0.2803
···
Divisor Countnumber_theory0.0000
Rossler Attractorchaos0.0000
Constant 0xFFnoise0.0000
z_conjugate
SourceDomainValue
Bearing Normalbearing0.3970
LIGO Livingstonastro0.3462
Logistic r=3.83 (Period-3 Window)chaos0.2515
···
fBm (Persistent)noise-0.6934
Bearing Innerbearing-0.5921
Brownian Walknoise-0.5870
z_primary
SourceDomainValue
Bearing Outerbearing0.4304
Bearing Innerbearing0.3286
Solar Wind IMFastro0.2987
···
Circle Map Quasiperiodicchaos-0.5538
Phyllotaxisbio-0.5405
Fibonacci Wordexotic-0.4819
z_reciprocal
SourceDomainValue
Critical Circle Mapchaos0.4014
Deep Earthquake P-wavegeophysics0.2290
Phyllotaxisbio0.1858
···
Mackey-Glassmedical-0.4151
Bearing Normalbearing-0.3913
Speech "Five"speech-0.2264

When It Lights Up

Septagonal is the most exotic geometry in the quasicrystal lens. The triple-conjugate ensemble (z_primary, z_conjugate, z_reciprocal) provides stronger specificity than single-ratio testing: all three roots must show coherence simultaneously for genuine 7-fold order. Septagonal completes the quasicrystal lens's coverage of crystallographically forbidden symmetries (5, 7, 8, 12-fold).

Open in Atlas
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