e_013310
plain-language theorem explainer
For the six-index slot (0,1,3,3,1,0) on Fin 4, the folded numerator m2Num equals eight times the closed-form kernel value explicitZ. Gravity analysts cite it when assembling the exact midpoint M2 TT identity in 4D Regge calculus. The proof is a single kernel decide on concrete integers.
Claim. For indices $a{=}0$, $b{=}1$, $c{=}3$, $d{=}3$, $i{=}1$, $j{=}0$ in $\mathrm{Fin}\,4$, the folded coupling numerator $m_2^{\mathrm{num}}(a,b,c,d,i,j)$ equals $8$ times the explicit kernel integer $Z(a,b,c,d,i,j)$.
background
In the 4D Regge midpoint analysis, two integer-valued kernels on six $\mathrm{Fin},4$ indices are compared. The numerator $m_2^{\mathrm{num}}$ is defined by folding a fixed coupling list: each term contributes an integer via a local contribution map, and the fold starts at zero. The comparison target is an explicit piecewise integer table $Z$ on the same six indices (sample clauses include $Z(0,0,1,1,2,2)=4$ and $Z(0,0,1,2,1,2)=-2$).
This module is chunk 1 of a 256-way kernel split that discharges $m_2^{\mathrm{num}}=8Z$ pointwise by decision procedures. The local setting is pure finite enumeration over $\mathrm{Fin},4^6$, not continuum GR; the identity is an algebraic certificate inside the discrete curvature bookkeeping.
proof idea
One-line decide on the fully concrete instance. Both sides reduce to closed integers: the left by evaluating the fold of contrib over couplingZList at $(0,1,3,3,1,0)$, the right by looking up explicitZ at those indices and multiplying by 8. No lemmas beyond kernel evaluation are invoked.
why it matters
Feeds the assembly theorem m2Num_eq_eight_explicitZ, which states $\forall a,b,c,d,i,j,, m_2^{\mathrm{num}}=8Z$ by exhaustive fin_cases over all six indices. Each chunk theorem such as this one supplies one concrete cell so the global identity can be stitched without a monolithic decide.
In the Recognition gravity stack this certifies the exact midpoint M2 TT numerator identity in 4D, a discrete curvature bookkeeping step toward the continuum limit. It does not itself invoke the forcing chain (T5–T8) or the Recognition Composition Law; it is infrastructure under the Regge analysis layer.
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