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Geometry definitions

Definitions for similarity dimension, box counting, generalized dimensions, singularity spectra, Poincaré distance, hyperbolic curvature, Laplace–Beltrami modes, inverse participation ratio, and the $E_{47}$ embedding boundary are consolidated in Fractals and Hyperbolic Geometry.

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Hardware-in-the-loop (HIL) validation status (2026-07-19)

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Linguistic entities and notation lock

Definitions for $\Sigma,K,\Psi,\Gamma,\Lambda,\Omega,\mathcal I,\mathcal M$, the lexical flow $A_t$, symbol matrix $w$, pre-grammar space $V^*$, and the distinction between historical $J/M$ notation and current Interpretation/Mnemosyne notation are maintained in the full Invariant Grammar monograph.

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Skyrmion constructs added

Definitions and status boundaries for $U$, $L_i$, $B$, $\mathbf n$, $Q$, $\mathcal O_{v_0}$, $M_{ab}(v_0)$, $c_4$, Derrick stationarity, and the RI correspondence are collected on Skyrmions.

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Computational definitions and implementation status

The canonical numerical realizations of $C$, $K$, $E_{47}$, $P_{47}$, the complement $Q$, contraction maps, spectra, residuals, and synthetic reference objects are catalogued in Python and Numerical Validation.

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Entities and Constructs

Canonical definitions for the K47/125 formalism and its invariant grammar.

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Algebraic entities

Carrier

$V_2$ is the spin-2 irreducible representation of $SU(2)$, with

$\dim V_2=5.$

The canonical carrier is

$\Sigma:=V_2^{\otimes3},\qquad \dim\Sigma=125.$

Total generators

$`J_a^{mathrm{tot}}=J_aotimes Iotimes I+Iotimes J_aotimes I+Iotimes Iotimes J_a,$$

for $a\in\{x,y,z\}$.

Casimir

$C=(J_x^{\mathrm{tot}})^2+(J_y^{\mathrm{tot}})^2+(J_z^{\mathrm{tot}})^2.$ It is Hermitian and acts by $j(j+1)$ on the spin-$j$ sector.

Isotypic sectors

$\Sigma\cong V_0\oplus3V_1\oplus5V_2\oplus4V_3\oplus3V_4\oplus2V_5\oplus V_6.$ The sector dimensions are $(1,9,25,28,27,22,13).$

Kernel selector

$K=(C-6I)(C-30I).$ It annihilates exactly the $j=2$ and $j=5$ isotypic sectors.

Protected sector

$`E_{47}:=ker K=W_2oplus W_5cong5V_2oplus2V_5,$$

$\dim E_{47}=47.$

Transient complement