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IndisputableMonolith.Gravity.Analysis.ReggeBlochFold4D

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Factorized Bloch fold for the 4D Regge (1,1) hinge orbit, with a zero-momentum consistency gate against the committed flat Hessian quadratic. Continuum and symbol analysts on the Freudenthal lattice cite it before multi-orbit folds and m² expansions. The module is mostly definitional packaging plus algebraic linearity and orbit-count identities.

claimOn the 4D Freudenthal lattice, the factorized Bloch fold over $(1,1)$ hinge slots equals the committed flat second-variation quadratic of that orbit at vanishing Bloch momentum $k=0$. The module supplies phased class-dots, the $(1,1)$ slot predicate, factorized slot terms, and the natural/real $(1,1)$ counts used in that gate.

background

This sits in the QG full-theory campaign for 4D Regge calculus on the Freudenthal (Kuhn) triangulation of the 4-cube. Upstream modules fix the 15-class edge stencil, triangle-hinge orbit types under $S_4$ (with complement), star deficit kernels, and the flat Hessian assembled from Heron area gradients with true zero-momentum weights, replacing the provisional weight-1 aggregate.

A Bloch fold packages the second variation as a momentum-dependent quadratic form on edge classes. The $(1,1)$ orbit is the shortest hinge type and the natural first consistency check: at $k=0$ phases drop out and the fold must recover the already-committed orbit quadratic from the flat Hessian assembly.

Sibling objects include coordinate masks, hinge bases, a phased class-dot (linear in the class vector), the $(1,1)$ predicate via pop-count, factorized slot terms, and natural/real counts of $(1,1)$ slots.

proof idea

Definition-heavy module with short algebraic lemmas, not a long tactic proof. It introduces mask and hinge-base coordinates, then a phased class-dot with additivity, scalar homogeneity, and a zero-momentum reduction to the unphased class-dot. The $(1,1)$ slot predicate is tied to a pop-count characterization. Factorized slot terms and the factorized $(1,1)$ Bloch fold are assembled from those pieces; natural and real $(1,1)$ counts support the zero-momentum consistency gate against the committed orbit quadratic. No continuum limit or multi-orbit sum is proved here.

why it matters in Recognition Science

This is the consistency gate named in the module doc: factorized fold at zero momentum recovers the committed $(1,1)$ orbit quadratic. Downstream, ReggeBlochAllOrbitSymbol4D consumes the same factorization pattern over all six $S_4$ hinge types; ReggeBlochM2Symbol4D expands the small-momentum ($m^2$) symbol of the $(1,1)$ fold; orbit-transport, star-edge-origin, local-incidence, and transported all-orbit modules import the fold API; the transported algebraic closer banks identities without claiming Einstein-Hilbert Tendsto. In the campaign ladder it sits after stencil, orbit classification, star kernels, and flat Hessian assembly, and before full multi-orbit Bloch symbols and continuum preflight.

scope and limits

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