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IndisputableMonolith.Gravity.Analysis.ReggeHinge4DStarKernel

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Defines the 4D Freudenthal hinge star: the finite set of cube translates whose simplices meet a fixed triangular hinge, with opposite/orthogonal edge classes and Gram data at flat. Gravity analysts cite it when assembling true-weight flat Hessians and Bloch folds. Structure is combinatorial enumeration plus algebraic identities on masks and edge pairings, not continuum analysis.

claimOn the 4D Freudenthal lattice, fix a seed triangular hinge. The star is the finite list of cube translates whose local hinge masks contain that hinge; its cardinality is fixed, and each star member carries opposite and orthogonal flat-square edge classes together with the associated Gram-determinant and apex-dot numerators at the flat background.

background

This module sits in the QG full-theory campaign after the 15-class edge stencil and the flat/dihedral hinge kernels. Those layers package Freudenthal incidence and the seed-hinge cosine data at flat; they never redefine the stencil API. The present file lifts from a single seed hinge to the full star of cubes that touch it.

A cube translate is a lattice shift of the reference 4-cube. Local hinge masks mark which triangle hinges live in each translate. A star member is one such translate that contains the seed hinge; starMembers enumerates them completely, with a proved length and cardinality. Opposite and orthogonal flat-square edge classes record how the two faces of the hinge sit relative to the remaining edges in each member, feeding Gram determinants and apex inner-product numerators used later as true weights.

Notation stays discrete and combinatorial: no continuum limit is taken here. The flat background is the same zero-curvature reference used by the dihedral and flat kernels upstream.

proof idea

Definition-and-enumeration module with supporting lemmas, not a single deep theorem. Cube translates and hinge masks are introduced first; membership is the predicate that a mask contains the seed hinge. Completeness and length of the star list are proved by exhaustive case analysis on the finite Freudenthal incidence table. Opposite/orthogonal edge-class maps and the Gram/apex identities are algebraic reductions on those finite tables, reusing the flat and dihedral kernels rather than re-deriving cosine expansions.

why it matters in Recognition Science

The star is the missing local assembly unit between seed-hinge kernels and global second-variation symbols. Downstream, ReggeFlat4DHessianAssembly consumes the per-orbit star deficit kernels with Heron area gradients to replace the provisional weight-1 aggregate of the edge stencil. Bloch modules (ReggeBlochFold4D, all-orbit and transported folds, local-incidence Path B) expand the star as a sum over cube-translate bases with phase decoration. The exact-action symbol module uses the same star data when checking that the true Regge Hessian annihilates vertex gauge modes and sends normalized TT to $-1/4$. The audit module re-imports this file for kernel checks. Without a committed star cardinality and opposite-edge Gram layer, the flat Hessian and continuum $m^2$ moments have no local support.

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