e_220321
plain-language theorem explainer
At multi-index (2,2,0,3,2,1) the Regge midpoint M2 numerator equals eight times the explicit Z kernel value. Gravity analysts cite this as one of the 256 finite-case checks that assemble the full 4D identity. The proof is a single kernel decide on the closed integer expressions.
Claim. For indices $a{=}2,\,b{=}2,\,c{=}0,\,d{=}3,\,i{=}2,\,j{=}1$ in $\mathbb{F}_4$, the midpoint $M_2$ numerator equals eight times the explicit integer kernel $Z$ at that multi-index: $m_2(2,2,0,3,2,1)=8\,Z(2,2,0,3,2,1)$.
background
In the 4D Regge midpoint analysis, the $M_2$ numerator is an integer-valued six-index array on $\mathbb{F}_4$. It is defined by folding a fixed coupling list: each term contributes an integer contrib and the fold accumulates the total. Independently, an explicit kernel $Z$ is given by a finite pattern-match table of small integers (entries such as $4$, $-2$, and so on).
The local module is chunk 10 of a 256-way case split: the claim is that the folded numerator equals eight times the table value at every multi-index. Upstream, m2Num is exactly that fold, and explicitZ is the table. The factor eight is the global normalization relating the summed coupling contributions to the closed kernel.
proof idea
One-line computational proof: decide. Both sides are closed integer expressions once the six Fin 4 arguments are concrete literals, so the kernel evaluates the fold defining the numerator and the pattern match defining $Z$, then checks equality with $8Z$. No lemmas are invoked beyond the definitions of the two sides.
why it matters
This is one atomic cell in the exhaustive verification that $m_2=8Z$ on all of $(\mathbb{F}_4)^6$. The parent theorem m2Num_eq_eight_explicitZ introduces six free Fin 4 indices and discharges them by nested fin_cases, each leaf citing a chunk identity of this form. That global equality is the algebraic content of the Regge exact midpoint $M_2$ TT identity in 4D: the numerator built from couplings collapses to a sparse explicit kernel. Within Recognition gravity, such exact discrete identities underwrite continuum limits and curvature bookkeeping on the causal lattice; they sit downstream of the forcing chain's $D=3$ spatial claim only insofar as the 4D spacetime scaffolding is fixed. No open sorry remains on this leaf.
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