e_023331
plain-language theorem explainer
For the six-index tuple (0,2,3,3,3,1) on Fin 4, the folded numerator m2Num equals eight times the explicit kernel value explicitZ. Gravity analysts cite this as one cell of the 4D Regge midpoint M2TT identity. The proof is a single kernel decide on the concrete integers.
Claim. For indices $(a,b,c,d,i,j)=(0,2,3,3,3,1)$ in $\mathrm{Fin}\,4$, the coupling-fold numerator equals eight times the explicit integer kernel: $m_2^{\mathrm{num}}(0,2,3,3,3,1)=8\,Z_{\mathrm{explicit}}(0,2,3,3,3,1)$.
background
This module is chunk 2 of a 256-cell kernel certification that the 4D Regge midpoint numerator matches an explicit closed form. The numerator $m_2^{\mathrm{num}}(a,b,c,d,i,j)$ is the fold of a fixed coupling list: each term contributes an integer weight depending on the six Fin-4 indices, summed from zero.
The comparison target $Z_{\mathrm{explicit}}$ is a piecewise integer table on the same six indices (sample values include $4$, $-2$, and other small constants on the listed patterns). The local claim is the scalar identity $m_2^{\mathrm{num}}=8,Z_{\mathrm{explicit}}$ at one concrete multi-index inside that table.
Upstream, both sides are pure definitions in the kernel-cert module; no analytic lemma is required beyond evaluating those definitions at fixed Fin-4 data.
proof idea
One-line computational proof: decide evaluates both integer sides at the literal indices $(0,2,3,3,3,1)$ and checks equality. No rewrite lemmas or induction; the kernel reduces the fold defining the numerator and the matching clause of the explicit table to concrete Int values and confirms $L=8R$.
why it matters
Parent theorem m2Num_eq_eight_explicitZ assembles every Fin-4 cell by nested fin_cases, discharging each cell with a chunk lemma of this form. Without the cell-wise equalities, the universal statement $m_2^{\mathrm{num}}=8,Z_{\mathrm{explicit}}$ on all six indices would not close.
In the gravity stack this identity is the algebraic backbone of the exact midpoint M2TT relation in 4D Regge analysis: it replaces a summed coupling expression by a sparse explicit kernel, which is what downstream curvature and continuum-limit arguments consume. It is bookkeeping inside the Recognition gravity layer rather than a T0–T8 forcing step, but it is load-bearing for any claim that the discrete midpoint action matches the certified closed form.
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