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IndisputableMonolith.Cosmology.LatticeBallEdges

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Exact edge ledger for the 2D L1 lattice ball under the polarized birth field: every 4-neighbour adjacency is classified as monochromatic (carried) or bichromatic (interface), with closed cardinalities for each class and for the total. Cosmology proofs that weight recognition cost by edge type cite this module. The argument is combinatorial enumeration over the four unit directions and the four axial boundary faces.

claimOn the 2D $L^1$ ball (diamond) of radius $t$, the ordered 4-neighbour edge set decomposes as the disjoint union of monochromatic carried edges and bichromatic interface edges along the birth-field spine. The module supplies exact finite cardinalities for the direction set, each axial boundary, the carried class, the interface class, and the total edge count.

background

The scale-adaptive coarsening engine grows its world on an $L^1$ ball, one rung per recognition cycle. In 2D that ball is the diamond $|x|+|y|\le t$. Neighbours are the four unit steps $(\pm 1,0)$ and $(0,\pm 1)$. Upstream, LatticeBallVolume closed the cell counts; PolarizedBirthDomains showed the forced conjugate-birth field ($+1$ on $x>0$, $-1$ on $x<0$, $0$ on the spine) is held in exactly three locked domains; PolarizedBirthInterface and PolarizedBirthInterfaceCount confined recognition activity to the spine and counted interface edges exactly.

What remained open was the complementary bulk ledger: how many monochromatic adjacencies sit inside each half-plane, and how the total edge count splits as interface plus carried. This module introduces the direction set, the four axial boundary slices, and the global edge set $E$, then pins their cardinalities over $\mathbb{N}$.

proof idea

Definition-first combinatorial module. It fixes the four unit directions and proves their cardinality is 4. It defines the global ordered-edge set $E$ by ranging over ball cells and admissible steps that stay inside the ball, together with the four axial boundary faces (positive/negative $x$ and $y$). Cardinality lemmas then count each boundary slice by a one-dimensional step formula, assemble the domain-set count, and obtain the total edge cardinality as a closed polynomial in the radius. The interface-versus-carried split is inherited from the polarized field already fixed upstream; this module only finishes the arithmetic of the full adjacency list.

why it matters in Recognition Science

Phase 54 in the cosmogenesis chain. Downstream, PolarizedBirthInterfaceCost weights this ledger by the recognition cost $J(x)=(x+x^{-1})/2-1$ (unique by the Recognition Composition Law / T5) evaluated at the phi-rung charge gap: carried monochromatic edges cost nothing in the ledger, interface bichromatic edges are paid. Without exact total = interface + carried counts, the cost theorem cannot convert sub-extensive interface geometry into an $O(1)$-per-cycle recognition bill while the world is $\Theta(t^2)$. The module therefore closes the last purely combinatorial gap between the polarized birth geometry and the costed coarsening ledger.

scope and limits

used by (1)

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