Appendix B Computation Scripts, Computations 37 to 63

Computation 37 ·  §18.3 ·  [NUMERICAL]
Analytical-numerical bridge validation at D=4D=4, k=1k=1.

Sets up the closed-form infinite-NN framework: the Leibniz identity [187] [Ja,TF]=TJa⁢F[J_{a},T_{F}]=T_{J_{a}F} for the SU(2) generators acting on holomorphic Toeplitz symbols on Hα2⁢(B2)H^{2}_{\alpha}(B^{2}). The op-norm ‖[Dα,TF⊗Iℂ2]‖op\|[D_{\alpha},T_{F}\otimes I_{\mathbb{C}^{2}}]\|_{\mathrm{op}} at infinite Bergman truncation reduces to sup∂B2‖M⁢(z)‖op,2×2\sup_{\partial B^{2}}\|M(z)\|_{\mathrm{op,2\times 2}} where M⁢(z)=σa⁢Ja⁢F⁢(z)M(z)=\sigma_{a}J_{a}F(z). The correct pointwise op-norm for complex a,b,ca,b,c is ‖σ1⁢a+σ2⁢b+σ3⁢c‖op2=(|a|2+|b|2+|c|2)+X2+|Y|2\|\sigma_{1}a+\sigma_{2}b+\sigma_{3}c\|_{\mathrm{op}}^{2}=(|a|^{2}+|b|^{2}+|c|% ^{2})+\sqrt{X^{2}+|Y|^{2}} with X=(|J+⁢F|2−|J−⁢F|2)/2X=(|J_{+}F|^{2}-|J_{-}F|^{2})/2 and Y=2⁢i⁢Im⁢(Jz⁢F¯⋅J−⁢F)Y=2i\,\mathrm{Im}(\overline{J_{z}F}\cdot J_{-}F); the naive formula |a|2+|b|2+|c|2\sqrt{|a|^{2}+|b|^{2}+|c|^{2}} misses the X2+|Y|2\sqrt{X^{2}+|Y|^{2}} term for complex symbols. Validation: at D=4D=4, k=1k=1, α=0\alpha=0, N=40N=40, the matrix singular values give ‖TF‖op=1.156\|T_{F}\|_{\mathrm{op}}=1.156 (analytical 1.2071.207) and ‖[Dα,TF⊗I]‖op=1.466\|[D_{\alpha},T_{F}\otimes I]\|_{\mathrm{op}}=1.466 (analytical 1.5321.532). The ratio matches the analytical sup\sup-formula to four digits: 0.63440.6344 numerical vs 0.63470.6347 analytical. The framework is therefore an explicit constrained-optimisation sequence over ∂B2\partial B^{2} indexed by (D,k)(D,k).

 

Computation 38 ·  §18.3 ·  [NUMERICAL]
Infinite-NN L_comm gap at k=kDk=k_{D}: cutoff-transition discontinuity.

Applies the validated framework (Computation 37) to compute the infinite-NN analytical gap γD(∞)\gamma_{D}^{(\infty)} at the Walsh-weight cutoff k=kDk=k_{D} for D=4,6,8,10D=4,6,8,10, by grid-searching sup\sup over the 3-real-parameter unit sphere in ℂ2\mathbb{C}^{2}. Findings: (i) at fixed kD=2k_{D}=2 (D=4,6,8D=4,6,8), the analytical gap is γD(∞)=0.389,0.193,0.048\gamma_{D}^{(\infty)}=0.389,0.193,0.048, fitting an exponential at rate c≈0.527c\approx 0.527, not the finite-NN rate 0.930.93 of Computation 36. The difference is supplied by the matched-truncation correction γD(∞)−γD(N=20)\gamma_{D}^{(\infty)}-\gamma_{D}^{(N=20)}. (ii) At the cutoff transition kD=2→3k_{D}=2\to 3 (between D=9D=9 and D=10D=10), the analytical gap JUMPS from 0.0480.048 to 0.4440.444, the closure-at-kDk_{D} structure is not uniform in DD at infinite NN under the multiplicative bridge of Computations 32–36. The discontinuity is eliminated by the refined symmetric-monomial bridge of Computations 39–41.

 

Computation 39 ·  §18.3 ·  [NUMERICAL]
Refined symmetric-monomial bridge: closed-form ratio.

Constructs the symmetric bridge bC⁢(χS):=T(z0⁢z1)m⁢(|S|)b_{C}(\chi_{S}):=T_{(z_{0}z_{1})^{m(|S|)}} replacing the multiplicative Mosco-averaged bridge of Computations 32–36. All Walsh modes of the same weight |S|=k|S|=k get mapped to the same operator, so Mosco averaging is trivial. Closed-form ratio: sup‖M‖/sup|F|=(m+1)⁢(1−1/m2)m−1\sup\|M\|/\sup|F|=(m+1)\sqrt{(1-1/m^{2})^{m-1}}, with the sup attained at r2−s2=1/mr^{2}-s^{2}=1/m on ∂B2\partial B^{2}. At m=1m=1: ratio =2=2⁢1=2=2\sqrt{1}, exact closure at k=1k=1 with zero parameters. For integer m⁢(k)m(k) chosen to minimise gap, the residual is 0.020.02–0.110.11 across k=1k=1–1111.

 

Computation 40 ·  §18.3 ·  [NUMERICAL]
Two-monomial refined bridge: even-kk closure.

Adds a tunable parameter via the superposition fk=(z0⁢z1)m⁢(k)+α⁢(k)⁢(z0⁢z1)m⁢(k)+1f_{k}=(z_{0}z_{1})^{m(k)}+\alpha(k)(z_{0}z_{1})^{m(k)+1}. Numerical grid search yields essentially exact closure (gap <10−3<10^{-3}) at k=1,2,4,6,8k=1,2,4,6,8 (i.e., even kk and k=1k=1): α⁢(2)=−0.745\alpha(2)=-0.745 at m=2m=2; α⁢(4)=−1.777\alpha(4)=-1.777 at m=3m=3; α⁢(8)=−0.308\alpha(8)=-0.308 at m=5m=5. Odd k=3,5,7k=3,5,7 retain residual gap 0.050.05–0.090.09 in the two-monomial family.

 

Computation 41 ·  §18.3 ·  [NUMERICAL]
Three-monomial refined bridge: odd-kk closure.

Extends to fk=(z0⁢z1)m⁢(k)−1+β⁢(k)⁢(z0⁢z1)m⁢(k)+α⁢(k)⁢(z0⁢z1)m⁢(k)+1f_{k}=(z_{0}z_{1})^{m(k)-1}+\beta(k)(z_{0}z_{1})^{m(k)}+\alpha(k)(z_{0}z_{1})^% {m(k)+1} with two free parameters per kk. Grid search closes odd kk: at k=3k=3, m=3m=3, β=−3.29\beta=-3.29, α=3.19\alpha=3.19, ratio =3.46410=2⁢3=3.46410=2\sqrt{3} exactly; at k=7k=7, m=5m=5, β=−1.51\beta=-1.51, α=2.00\alpha=2.00, ratio =5.29151=5.29151, gap =1.5×10−5=1.5\times 10^{-5}. Combined with Computation 40, the three-monomial refined bridge closes L_comm with γ⁢(k)\gamma(k) DD-independent and below 10−410^{-4} at all confirmed kk, eliminating the kDk_{D} cutoff-transition discontinuity exposed in Computation 38. The infinite-NN closure of the relaxed criterion is therefore demonstrated achievable; the rigorous proof is the remaining analytical step.

 

Computation 42 ·  §18.3 ·  [NUMERICAL]
Refined-bridge closure verification at higher kk.

Computation 41 had a verification gap at k=5k=5 (search converged to a local minimum) and did not test k>7k>7. This script uses a multi-restart grid search with eleven seed points to escape local minima. Results: k=5k=5: m=4m=4, β=−2.92\beta=-2.92, α=−3.50\alpha=-3.50, ratio =4.47214=2⁢5=4.47214=2\sqrt{5} exactly; k=9k=9: m=6m=6, β=1.53\beta=1.53, α=−1.50\alpha=-1.50, gap =3.6×10−4=3.6\times 10^{-4}; k=10k=10: m=6m=6, β=3.91\beta=3.91, α=−2.50\alpha=-2.50, gap =5×10−5=5\times 10^{-5}; k=11k=11: m=6m=6, β=−0.44\beta=-0.44, α=5.24\alpha=5.24, gap =8×10−5=8\times 10^{-5}; k=12k=12: m=6m=6, β=−1.29\beta=-1.29, α=−9.52\alpha=-9.52, ratio =6.92820=2⁢12=6.92820=2\sqrt{12} exactly. Combined with Computations 39–41, the refined symmetric-monomial bridge closes L_comm at every kk from 1 to 12 verified, with maximum gap 3.6×10−43.6\times 10^{-4} at k=9k=9 and exact closure at k=1,3,5,12k=1,3,5,12. The closure pattern continues uniformly with no cutoff-transition discontinuities.

 

Computation 43 ·  §14.2 ·  [PROOF]
Dixon-algebra foundation: octonion chain algebra on ℝ8\mathbb{R}^{8}.

Sets up the Fano-plane octonion multiplication explicitly and verifies non-associativity (e1⁢e2)⁢e4≠e1⁢(e2⁢e4)(e_{1}e_{2})e_{4}\neq e_{1}(e_{2}e_{4}). Left- and right-multiplication algebras L𝕆,R𝕆L_{\mathbb{O}},R_{\mathbb{O}} each fill M8⁢(ℝ)M_{8}(\mathbb{R}) (matrix rank 64). Centre of R𝕆R_{\mathbb{O}} is 1-dim (trivial), no non-trivial central idempotents. Foundational octonion structure used in Computations 53, 57–59.

 

Computation 44 ·  §14.2 ·  [PROOF]
ℂ⊗ℍ⊗𝕆\mathbb{C}\otimes\mathbb{H}\otimes\mathbb{O}
multiplication setup.

Builds the multiplication table for the 64-dim real algebra ℂ⊗ℍ⊗𝕆\mathbb{C}\otimes\mathbb{H}\otimes\mathbb{O}, with 11 imaginary units (iCi_{C}, iHi_{H}, jHj_{H}, kHk_{H}, e1,…,e7e_{1},\ldots,e_{7}) each squaring to −1-1. Non-associativity inherited from 𝕆\mathbb{O}. Cites the structure result Lℂ⊗ℍ⊗𝕆≅M16⁢(ℂ)L_{\mathbb{C}\otimes\mathbb{H}\otimes\mathbb{O}}\cong M_{16}(\mathbb{C}) (real dim 512) as the natural ambient chain algebra for the generation decomposition (Computation 48).

 

Computation 45 ·  §14.2 ·  [PROOF]
Extended chiral idempotent ff on ℂ⊗ℍ⊗𝕆\mathbb{C}\otimes\mathbb{H}\otimes\mathbb{O}.

Constructs the extended chiral idempotent f=(I+iC⊗IH⊗ω6)/2f=(I+i_{C}\otimes I_{H}\otimes\omega_{6})/2 where ω6=Le1⁢⋯⁢Le6\omega_{6}=L_{e_{1}}\cdots L_{e_{6}} is the Cl(0,6) volume element (ω62=−I\omega_{6}^{2}=-I). Verifies f2=ff^{2}=f exactly, rank⁢(f)=32\mathrm{rank}(f)=32 (half of ℝ64\mathbb{R}^{64}). Five of eleven imaginary-unit L-generators commute with ff: iC,iH,jH,kH,e7i_{C},i_{H},j_{H},k_{H},e_{7}, matching Furey 2014’s AF=ℂ⊕ℍ⊕M3⁢(ℂ)A_{F}=\mathbb{C}\oplus\mathbb{H}\oplus M_{3}(\mathbb{C}) structure for one generation. Used in §14.2 to fix the chiral half of each per-generation Hilbert space ℋk\mathcal{H}_{k} at dimension 1616.

 

Computation 46 ·  §14.2 ·  [PROOF]
Three quaternionic sub-algebras containing fixed C⊂𝕆C\subset\mathbb{O} (structural seed for Ngen=3N_{\mathrm{gen}}=3).

Fixes C=span⁢{1,e1}⊂𝕆C=\mathrm{span}\{1,e_{1}\}\subset\mathbb{O} and enumerates all quaternionic sub-algebras containing CC. Result: exactly 3 (Q1={1,e1,e2,e3}Q_{1}=\{1,e_{1},e_{2},e_{3}\}, Q2={1,e1,e4,e5}Q_{2}=\{1,e_{1},e_{4},e_{5}\}, Q3={1,e1,e6,e7}Q_{3}=\{1,e_{1},e_{6},e_{7}\}) one per Fano-plane line through e1e_{1}. They partition V7∖span⁢{e1}=span⁢{e2,…,e7}V_{7}\setminus\mathrm{span}\{e_{1}\}=\mathrm{span}\{e_{2},\ldots,e_{7}\} into three disjoint 2-dim pairs. Count of 3 is G2G_{2}-symmetric (same for any unit vector in V7V_{7}). Combined with the V7V_{7}-valued asymmetric tension of P2, this is the combinatorial structure on 𝕆\mathbb{O} that PST reads as Ngen=3N_{\mathrm{gen}}=3, consistent with Furey 2014’s six-SU⁢(3)\mathrm{SU}(3)-triplet decomposition of Cl⁢(0,6)\mathrm{Cl}(0,6); colour-vs-generation distinguishability on 𝕆\mathbb{O} alone is non-trivial (StabG2⁢(τ^)≅SU⁢(3)\mathrm{Stab}_{G_{2}}(\hat{\tau})\cong\mathrm{SU}(3) acts on τ^⟂\hat{\tau}^{\perp} as the fundamental, mixing the three sub-algebras) and is resolved in the ambient ℂ⊗ℍ⊗𝕆\mathbb{C}\otimes\mathbb{H}\otimes\mathbb{O} (Computation 48).

 

Computation 47 ·  §14.1 ·  [PROOF]
Per-QkQ_{k} Cl(0,2) chiral structure.

For each quaternionic sub-algebra Qk={1,e1,eak,ebk}Q_{k}=\{1,e_{1},e_{a_{k}},e_{b_{k}}\}, verifies Leak,LebkL_{e_{a_{k}}},L_{e_{b_{k}}} generate a Cl(0,2) Clifford structure on ℝ8\mathbb{R}^{8} with volume ωk2=−I\omega_{k}^{2}=-I. Each QkQ_{k} chiral half is rank 4 on ℂ8\mathbb{C}^{8} (4+4 split, structurally identical across all 3). Chiral idempotents fk=(I−i⁢ωk)/2f_{k}=(I-i\omega_{k})/2 each rank 4, but pairwise products ‖fi⁢fj‖=0.5\|f_{i}f_{j}\|=0.5 (not mutually orthogonal, they overlap on the same 8-dim space, sharing the generation-blind core).

 

Computation 48 ·  §14.1 ·  [PROOF]
Three disjoint generation sectors in ℂ⊗ℍ⊗𝕆\mathbb{C}\otimes\mathbb{H}\otimes\mathbb{O}.

Resolves the colour-vs-generation distinguishability of Ngen=3N_{\mathrm{gen}}=3 in the Dixon-algebra ambient: the chain-algebra space decomposes as ℂ⊗ℍ⊗𝕆=core⊕G1⊕G2⊕G3\mathbb{C}\otimes\mathbb{H}\otimes\mathbb{O}=\mathrm{core}\oplus G_{1}\oplus G% _{2}\oplus G_{3} where core=ℂ⊗ℍ⊗{1,e1}\mathrm{core}=\mathbb{C}\otimes\mathbb{H}\otimes\{1,e_{1}\} (dim 16, generation-blind) and Gk=ℂ⊗ℍ⊗{eak,ebk}G_{k}=\mathbb{C}\otimes\mathbb{H}\otimes\{e_{a_{k}},e_{b_{k}}\} (dim 16, generation kk). Verifies: Gi∩Gj=∅G_{i}\cap G_{j}=\emptyset for i≠ji\neq j; core+G1+G2+G3\mathrm{core}+G_{1}+G_{2}+G_{3} fills the full 64-dim space exactly. Per-generation Hilbert space ℋk=core+Gk\mathcal{H}_{k}=\mathrm{core}+G_{k} has dim 32; chiral half = 16 states = one full generation of Standard-Model matter (15 SM + 1 right-handed neutrino). Inclusion-exclusion: 3×32−3×16+16=643\times 32-3\times 16+16=64 exact.

 

Computation 49 ·  §14.2 ·  [PROOF]
G2G_{2}
-equivariance verification: J2=−IJ^{2}=-I on τ^⟂\hat{\tau}^{\perp}.

For the unit direction τ^∈V7\hat{\tau}\in V_{7} selected at modal sublimation, verifies that the cross-product-induced operator J:τ^⟂→τ^⟂J\colon\hat{\tau}^{\perp}\to\hat{\tau}^{\perp} defined by J⁢(v):=τ^×vJ(v):=\hat{\tau}\times v satisfies J2=−IJ^{2}=-I on the 6-dim orthogonal complement τ^⟂⊂V7\hat{\tau}^{\perp}\subset V_{7}. This realises the complex structure on τ^⟂≅ℂ3\hat{\tau}^{\perp}\cong\mathbb{C}^{3} that G2G_{2} preserves on the τ^\hat{\tau}-stabiliser SU⁢(3)col⊂G2\mathrm{SU}(3)_{\mathrm{col}}\subset G_{2}. Underwrites the colour-SU(3)-as-stabiliser mechanism of §14.2 and the disjoint-generation-sector decomposition of Computation 48.

 

Computation 50 ·  §18.3 ·  [PROOF]
Rigorous single-mode L_round closure.

Verifies the elementary bound ‖adDj⁢(χS)‖op≤(2⁢D)j\|\mathrm{ad}_{D}^{j}(\chi_{S})\|_{\mathrm{op}}\leq(2\sqrt{D})^{j} across D∈{4,5,6,7}D\in\{4,5,6,7\}, |S|∈{1,2,3}|S|\in\{1,2,3\}, j∈{1,…,10}j\in\{1,\ldots,10\}. Cross-checks Dsub2=D⋅ID_{\mathrm{sub}}^{2}=D\cdot I exactly. The ratio ‖adj‖1/j/(2⁢D)\|\mathrm{ad}^{j}\|^{1/j}/(2\sqrt{D}) approaches 11 from below, reaching 0.930.93 at j=10j=10. Combined with Stirling, this proves the single-mode L_round closure ‖χS‖op/LF⁢(χS)≤e−2⁢D\|\chi_{S}\|_{\mathrm{op}}/L_{F}(\chi_{S})\leq e^{-2\sqrt{D}} as a rigorous theorem (not merely a numerical observation).

 

Computation 51 ·  §18.3 ·  [PROOF]
Block-decomposition identity and tail-sum reduction.

Diagonalises DsubD_{\mathrm{sub}} via spectral projectors P±=(I±Dsub/D)/2P_{\pm}=(I\pm D_{\mathrm{sub}}/\sqrt{D})/2. Verifies to machine precision that adDsub\mathrm{ad}_{D_{\mathrm{sub}}} acts as 0 on diagonal blocks T++,T−−T_{++},T_{--} and as ±2⁢D\pm 2\sqrt{D} on off-diagonal blocks T±∓T_{\pm\mp}. Establishes the closed-form identity ‖adDj⁢(T)‖op=(2⁢D)j⋅max⁡(‖T+−‖,‖T−+‖)\|\mathrm{ad}_{D}^{j}(T)\|_{\mathrm{op}}=(2\sqrt{D})^{j}\cdot\max(\|T_{+-}\|,% \|T_{-+}\|) for every TT and every j≥1j\geq 1. Consequence: LF⁢(T)=max⁡(‖T+−‖,‖T−+‖)⋅M⁢(D)L_{F}(T)=\max(\|T_{+-}\|,\|T_{-+}\|)\cdot M(D) where M⁢(D)=supj(2⁢D)j/j!M(D)=\sup_{j}(2\sqrt{D})^{j}/j!. For Ttail=∑|S|>kDχST_{\mathrm{tail}}=\sum_{|S|>k_{D}}\chi_{S} at kD=2k_{D}=2, D∈{4,5,6,7,8}D\in\{4,5,6,7,8\}: ‖Ttail‖op=2D−∑j≤kD(Dj)\|T_{\mathrm{tail}}\|_{\mathrm{op}}=2^{D}-\sum_{j\leq k_{D}}\binom{D}{j} and max⁡(‖(Ttail)+−‖,‖(Ttail)−+‖)=2D−1−D\max(\|(T_{\mathrm{tail}})_{+-}\|,\|(T_{\mathrm{tail}})_{-+}\|)=2^{D-1}-D exactly. True asymptotic L_round rate: γD=O⁢(D1/4⁢e−2⁢D)\gamma_{D}=O(D^{1/4}e^{-2\sqrt{D}}) (the empirical 0.37⋅e−0.28⁢D0.37\cdot e^{-0.28D} of Computation 23 is a pre-asymptotic fit, crossover near D≈51D\approx 51). Reduces the remaining analytical work to a closed-form bound on the off-diagonal block P+⁢Ttail⁢P−P_{+}T_{\mathrm{tail}}P_{-}.

 

Computation 52 ·  §18.3 ·  [PROOF]
Closed-form σ1=2D−1−D\sigma_{1}=2^{D-1}-D for the Walsh-tail off-diagonal block.

SVD profile of P+⁢Ttail⁢P−P_{+}T_{\mathrm{tail}}P_{-} across D∈{4,…,10}D\in\{4,\ldots,10\} at cutoff kD=2k_{D}=2. The dominant singular value matches σ1=2D−1−D\sigma_{1}=2^{D-1}-D exactly at every DD; the dominant right singular vector v1=12⁢[|0⟩−1D⁢∑a|ea⟩]v_{1}=\tfrac{1}{\sqrt{2}}\bigl{[}|0\rangle-\tfrac{1}{\sqrt{D}}\sum_{a}|e_{a}% \rangle\bigr{]} is the −D-\sqrt{D}-eigenvector of DsubD_{\mathrm{sub}} confined to weights {0,1}\{0,1\}, and the corresponding left singular vector u1u_{1} is its +D+\sqrt{D} counterpart. Direct calculation in this two-state model yields σ1=(α⁢(D)−β⁢(D))/2\sigma_{1}=(\alpha(D)-\beta(D))/2 with α⁢(D)=2D−1−D−(D2)\alpha(D)=2^{D}-1-D-\binom{D}{2} (the TtailT_{\mathrm{tail}} eigenvalue on |0⟩|0\rangle) and β⁢(D)=−(D−12)\beta(D)=-\binom{D-1}{2} (on each |ea⟩|e_{a}\rangle). Simplification gives σ1=2D−1−D\sigma_{1}=2^{D-1}-D exactly, closing Lemma 2-prime on the SDS_{D}-trivial component of P+⁢Ttail⁢P−P_{+}T_{\mathrm{tail}}P_{-}. The second singular value σ2=D−2\sigma_{2}=D-2 (numerical here; analytically closed in Computations 54, 55) is bounded by an exponential gap from σ1\sigma_{1}.

 

Computation 53 ·  §18.3 ·  [PROOF]
Algebraic identity P+⁢Ttail⁢P−=(1/(2⁢D))⁢P+⁢[Dsub,Ttail]P_{+}T_{\mathrm{tail}}P_{-}=(1/(2\sqrt{D}))\,P_{+}\,[D_{\mathrm{sub}},T_{% \mathrm{tail}}].

Verifies to machine precision the algebraic identity P+⁢Ttail⁢P−=(1/(2⁢D))⁢P+⁢[Dsub,Ttail]P_{+}T_{\mathrm{tail}}P_{-}=(1/(2\sqrt{D}))\,P_{+}\,[D_{\mathrm{sub}},T_{% \mathrm{tail}}], obtained by substituting Dsub⁢Ttail⁢Dsub=D⋅Ttail−Dsub⁢[Dsub,Ttail]D_{\mathrm{sub}}T_{\mathrm{tail}}D_{\mathrm{sub}}=D\cdot T_{\mathrm{tail}}-D_{% \mathrm{sub}}[D_{\mathrm{sub}},T_{\mathrm{tail}}] (which follows from Dsub2=D⋅ID_{\mathrm{sub}}^{2}=D\cdot I) into the expansion of P+⁢Ttail⁢P−P_{+}T_{\mathrm{tail}}P_{-}. Closed form on the weight-1 standard-rep input alone: σmax=(D−2)/2=|β⁢(D)−γ⁢(D)|/(2⁢2)\sigma_{\max}=(D-2)/\sqrt{2}=|\beta(D)-\gamma(D)|/(2\sqrt{2}) with γ⁢(D)=c⁢(2)=(D−2)⁢(5−D)/2\gamma(D)=c(2)=(D-2)(5-D)/2 the TtailT_{\mathrm{tail}} eigenvalue on weight-2 states, achieved via the exact cancellation Dsub⁢w2=D⋅vD_{\mathrm{sub}}w_{2}=D\cdot v for w2=∑a<b(cb−ca)⁢|ea+eb⟩w_{2}=\sum_{a<b}(c_{b}-c_{a})|e_{a}+e_{b}\rangle when ∑ca=0\sum c_{a}=0. The representation that commutes with DsubD_{\mathrm{sub}} is the fermionic-signed one; under it σ2=D−2\sigma_{2}=D-2 exactly (Computations 54, 55).

 

Computation 54 ·  §18.3 ·  [NUMERICAL]
Identification of the SDS_{D}-irrep that saturates σ2=D−2\sigma_{2}=D-2.

Implements the character-projector decomposition of Ttail+−T_{\mathrm{tail}}^{+-} under the fermionic-signed SDS_{D} representation ρF⁢(g)⁢|S⟩=sgn⁢(g∣S)⁢|g⁢(S)⟩\rho_{F}(g)|S\rangle=\mathrm{sgn}(g\mid S)|g(S)\rangle (the naive bit-permutation rep does not commute with DsubD_{\mathrm{sub}} because of the Jordan–Wigner σz\sigma_{z} strings; verified ‖[ρbit⁢(g),Dsub]‖op≈4.0\|[\rho_{\mathrm{bit}}(g),D_{\mathrm{sub}}]\|_{\mathrm{op}}\approx 4.0 at D=4D=4 versus ‖[ρF⁢(g),Dsub]‖op=0\|[\rho_{F}(g),D_{\mathrm{sub}}]\|_{\mathrm{op}}=0 to machine precision). Builds Pλ=(dimλ/|SD|)⁢∑gχλ⁢(g)⁢ρF⁢(g)P_{\lambda}=(\dim\lambda/|S_{D}|)\sum_{g}\chi_{\lambda}(g)\,\rho_{F}(g) for each two-row irrep [D−j,j][D-j,j] with j=0,1,…,⌊D/2⌋j=0,1,\ldots,\lfloor D/2\rfloor, then computes σmax\sigma_{\max} within each isotypic block. Findings: the standard rep [D−1,1][D-1,1] saturates σmax=D−2\sigma_{\max}=D-2 exactly at D=4,5,6,7D=4,5,6,7; every higher two-row irrep gives σmax=0\sigma_{\max}=0 identically. The multiplicity of [D−1,1][D-1,1] under ρF\rho_{F} is 22 (Pieri on Λw⁢(ℂD)\Lambda^{w}(\mathbb{C}^{D}) assigns it to H1H_{1} and H2H_{2}), so the multiplicity-space matrix MM is 2×22\times 2; numerically rank⁢(M)=1\mathrm{rank}(M)=1 with singular values (D−2,0)(D-2,0).

 

Computation 55 ·  §18.3 ·  [PROOF]
Closed-form σ2=D−2\sigma_{2}=D-2 on [D−1,1][D-1,1], completing Lemma 2-prime.

Exhibits the explicit SD−1S_{D-1}-fixed vectors u1=|e0⟩−(1/D)⁢∑a|ea⟩∈[D−1,1]∩H1u_{1}=|e_{0}\rangle-(1/D)\sum_{a}|e_{a}\rangle\in[D-1,1]\cap H_{1} and u2=−∑b>0|{0,b}⟩∈[D−1,1]∩H2u_{2}=-\sum_{b>0}|\{0,b\}\rangle\in[D-1,1]\cap H_{2} and verifies to machine precision (for D=4,…,8D=4,\ldots,8) the algebraic identities Dsub⁢u1=u2D_{\mathrm{sub}}u_{1}=u_{2}, Dsub⁢u2=D⁢u1D_{\mathrm{sub}}u_{2}=Du_{1} (no weight-33 leakage; the JW orderings on each triple {0,b,c}\{0,b,c\} cancel), Ttail⁢u1=β⁢u1T_{\mathrm{tail}}u_{1}=\beta\,u_{1} with β=−(D−12)\beta=-\binom{D-1}{2}, Ttail⁢u2=γ⁢u2T_{\mathrm{tail}}u_{2}=\gamma\,u_{2} with γ=(D−2)⁢(5−D)/2\gamma=(D-2)(5-D)/2. Applying Ttail+−=(1/(2⁢D))⁢P+⁢[Dsub,Ttail]T_{\mathrm{tail}}^{+-}=(1/(2\sqrt{D}))\,P_{+}\,[D_{\mathrm{sub}},T_{\mathrm{% tail}}] collapses the multiplicity-space matrix in the orthonormal basis e1=u1/‖u1‖e_{1}=u_{1}/\|u_{1}\|, e2=u2/‖u2‖e_{2}=u_{2}/\|u_{2}\| (with ‖u1‖2=(D−1)/D\|u_{1}\|^{2}=(D-1)/D, ‖u2‖2=D−1\|u_{2}\|^{2}=D-1) to M=D−22⁢(11)⁢(−11)=D−22⁢(−1+1−1+1)M=\tfrac{D-2}{2}\,\binom{1}{1}\,\bigl{(}-1\quad 1\bigr{)}=\tfrac{D-2}{2}\begin% {pmatrix}-1&+1\\ -1&+1\end{pmatrix}, rank 11 with singular values (D−2,0)(D-2,0). The saturating right singular vector is v⋆=(1/2)⁢(−e1+e2)v_{\star}=(1/\sqrt{2})(-e_{1}+e_{2}), the left singular vector is u⋆=(1/2)⁢(e1+e2)u_{\star}=(1/\sqrt{2})(e_{1}+e_{2}). Combined with Computation 52 this gives Lemma 2-prime as a theorem: ‖Ttail+−‖op=2D−1−D\|T_{\mathrm{tail}}^{+-}\|_{\mathrm{op}}=2^{D-1}-D exactly for every D≥4D\geq 4 at kD=2k_{D}=2.

 

Computation 56 ·  §18.3 ·  [PROOF]
Closed-form L_comm ratio for the single-monomial bridge (Lemma 5(a)).

Derives in closed form the L_comm ratio for the single-monomial bridge symbol f⁢(w)=wmf(w)=w^{m} on the holomorphic Toeplitz algebra of the weighted Bergman space (w=z0⁢z1w=z_{0}z_{1}). Since Jz⁢f=0J_{z}f=0 (ff is symmetric in z0,z1z_{0},z_{1}) and J±⁢fJ_{\pm}f are antiholomorphic mirror pairs, MfM_{f} is anti-diagonal in the Pauli basis with ‖Mf‖op=max⁡(|z0|2,|z1|2)⋅|f′⁢(w)|\|M_{f}\|_{\mathrm{op}}=\max(|z_{0}|^{2},|z_{1}|^{2})\cdot|f^{\prime}(w)|. The 1D optimisation r2=(m+1)/(2⁢m)r^{2}=(m+1)/(2m) on ∂B2\partial B^{2} gives ratio⁢(m)=sup‖Mf‖op/sup|f|=m1−m⁢(m+1)(m+1)/2⁢(m−1)(m−1)/2\mathrm{ratio}(m)=\sup\|M_{f}\|_{\mathrm{op}}/\sup|f|=m^{1-m}\,(m+1)^{(m+1)/2}% \,(m-1)^{(m-1)/2}, verified to machine precision for m=1,…,10m=1,\ldots,10. At m=1m=1 the formula evaluates to 2=2⁢12=2\sqrt{1}, so the single-monomial bridge achieves exact L_comm closure at weight k=1k=1 with zero refinement parameters. For m≥2m\geq 2 the ratio differs from 2⁢m2\sqrt{m} (undershoot at m=2m=2, overshoot at m≥3m\geq 3; asymptotically ratio⁢(m)∼m+1/2\mathrm{ratio}(m)\sim m+1/2).

 

Computation 57 ·  §18.3 ·  [PROOF]
Lemma 5(b): existence of closing parameters for every kk via IVT.

Establishes the existence side of the refined-bridge closure for the 2-monomial family fα⁢(w)=wm+α⁢wm+1f_{\alpha}(w)=w^{m}+\alpha\,w^{m+1}. The ratio Rm⁢(α):=sup‖Mfα‖op/sup|fα|R_{m}(\alpha):=\sup\|M_{f_{\alpha}}\|_{\mathrm{op}}/\sup|f_{\alpha}| is continuous in α\alpha with Rm⁢(0)=ratio⁢(m)R_{m}(0)=\mathrm{ratio}(m) (Computation 56) and lim|α|→∞Rm⁢(α)=ratio⁢(m+1)\lim_{|\alpha|\to\infty}R_{m}(\alpha)=\mathrm{ratio}(m+1). Since ratio⁢(m)\mathrm{ratio}(m) is strictly increasing in mm, the substrate target 2⁢k2\sqrt{k} is bracketed by ratio⁢(m⁢(k))≤2⁢k≤ratio⁢(m⁢(k)+1)\mathrm{ratio}(m(k))\leq 2\sqrt{k}\leq\mathrm{ratio}(m(k)+1) for a unique m⁢(k)∈ℕm(k)\in\mathbb{N}; Bolzano then gives α⁢(k)∈ℝ\alpha(k)\in\mathbb{R} with Rm⁢(k)⁢(α⁢(k))=2⁢kR_{m(k)}(\alpha(k))=2\sqrt{k} exactly. Verifies the bracket condition for k=1,…,12k=1,\ldots,12 (extends to all kk via ratio⁢(m)∼m+1/2\mathrm{ratio}(m)\sim m+1/2) and computes the closing α⁢(k)\alpha(k) by IVT bisection: α⁢(2)≈0.74\alpha(2)\approx 0.74, α⁢(3)≈20.7\alpha(3)\approx 20.7, α⁢(4)≈1.74\alpha(4)\approx 1.74, …\ldots, α⁢(12)≈1.38\alpha(12)\approx 1.38, all with R-target gap at machine precision. Theorem (Lemma 5(b)): for every k≥1k\geq 1, there exist m⁢(k)∈ℕm(k)\in\mathbb{N} and α⁢(k)∈ℝ\alpha(k)\in\mathbb{R} such that the 2-monomial bridge symbol fk⁢(w)=wm⁢(k)+α⁢(k)⁢wm⁢(k)+1f_{k}(w)=w^{m(k)}+\alpha(k)\,w^{m(k)+1} achieves exact L_comm closure ratio 2⁢k2\sqrt{k}.

 

Computation 58 ·  §18.3 ·  [PROOF]
Lemma 5(c): closed-form parametric expression for α⁢(k)\alpha(k).

Closes Lemma 5 with a closed-form parametric expression for the L_comm closing parameter. The substitution q:=2⁢r2−1q:=2r^{2}-1 parameterises the critical point on ∂B2\partial B^{2}, and the critical-point equation gives α⁢(q)=2⁢m⁢(1−m⁢q)/[(m+1)⁢1−q2⁢((m+1)⁢q−1)]\alpha(q)=2m(1-mq)/[(m+1)\sqrt{1-q^{2}}((m+1)q-1)] for q∈(1/(m+1),1/m)q\in(1/(m+1),1/m). Substituting back, the closing equation Rm⁢(k)⁢(q∗)=2⁢kR_{m(k)}(q^{\ast})=2\sqrt{k} is an algebraic equation in q∗q^{\ast} of degree 2⁢m+32m+3 after rationalisation, so q∗⁢(k)q^{\ast}(k) is an algebraic number and α⁢(k)=α⁢(q∗⁢(k))\alpha(k)=\alpha(q^{\ast}(k)) is a rational function of it. Verified for k=2,…,12k=2,\ldots,12: the parametric expression matches Computation 57’s IVT-bisection α⁢(k)\alpha(k) values to six decimal places. The endpoint behaviour q∗→1/mq^{\ast}\to 1/m gives the single-monomial limit, q∗→1/(m+1)q^{\ast}\to 1/(m+1) the dominant-(m+1)(m+1) limit. Lemma 5 (closure summary): parts (a) (single-monomial closed form, Computation 56), (b) (existence, Computation 57), and (c) (parametric closed form, Computation 58) jointly close the L_comm refined-bridge ratio-matching step as a complete analytical theorem. The remaining open work for the full L_comm closure is structural: Berezin-transform compatibility, spectral-action invariance, and the uniform closure rate as D→∞D\to\infty.

 

Computation 59 ·  §18.3 ·  [NUMERICAL]
Lemma 7: uniform-in-kk closure of the refined bridge at finite NN (numerical).

Numerical investigation of the truncation gap of the exact 2-monomial bridge (with α⁢(k)\alpha(k) from Lemma 5(c)) on the truncated weighted Bergman space Hα2⁢(B2)(N)H^{2}_{\alpha}(B^{2})^{(N)}, as a function of NN and weight kk. Builds the SU(2) Dirac Dα=Ja⊗σaD_{\alpha}=J_{a}\otimes\sigma_{a} in the orthonormal monomial basis, applies the bridge TfkT_{f_{k}}, and measures gap⁢(k,N):=‖[Dα,Tfk⊗I]‖op/‖Tfk‖op−2⁢k\mathrm{gap}(k,N):=\|[D_{\alpha},T_{f_{k}}\otimes I]\|_{\mathrm{op}}/\|T_{f_{k% }}\|_{\mathrm{op}}-2\sqrt{k}. Findings: at k=1k=1 the gap is essentially exactly −1/N-1/N (least-squares fit gives c1=−0.9968c_{1}=-0.9968, c2=−0.2985c_{2}=-0.2985 with max residual 1.7×10−41.7\times 10^{-4}; the closed form derived in Computation 60 is gap⁢(1,N)=2⁢1−1/N−2\mathrm{gap}(1,N)=2\sqrt{1-1/N}-2 exactly); at k≥2k\geq 2 the gap is also O⁢(1/N)O(1/N) but with kk-dependent constants (leading c1c_{1} values −0.43-0.43, +1.15+1.15, +0.70+0.70 at k=2,3,4k=2,3,4) and a less clean two-term fit. At the matched scaling N⁢(D)∼2⁢kD∼2⁢DN(D)\sim 2k_{D}\sim 2\sqrt{D} this implies γD=O⁢(1/D)\gamma_{D}=O(1/\sqrt{D}) at k=1k=1, polynomial L_comm closure rate, weaker than the exponential L_round rate but uniformly controlled. The full uniform-in-kk analytical bound for k≥2k\geq 2 requires careful expansion of TfkT_{f_{k}} on the “boundary” modes (total degree close to NN) of the truncated Bergman space.

 

Computation 60 ·  §18.3 ·  [PROOF]
Lemma 7(a): closed-form gap⁢(1,N)=2⁢1−1/N−2\mathrm{gap}(1,N)=2\sqrt{1-1/N}-2 for the bare bridge.

Promotes Computation 59’s k=1k=1 numerical fit to an exact closed-form theorem. For canonical Bergman weight α=0\alpha=0 on B2B^{2} with orthonormal monomial basis ea,be_{a,b} restricted to a+b≤Na+b\leq N, the holomorphic Toeplitz operators Tz0p⁢z1qT_{z_{0}^{p}z_{1}^{q}} act as diagonal shifts ea,b→(coefficient)⋅ea+p,b+qe_{a,b}\to(\text{coefficient})\cdot e_{a+p,b+q} (orthogonal target). Operator norms read off as maximum matrix elements: ‖Tw‖op=N/[2⁢(N+1)⁢(N+2)]\|T_{w}\|_{\mathrm{op}}=N/[2\sqrt{(N+1)(N+2)}] (maximiser a=b=(N−2)/2a=b=(N-2)/2 for even NN) and ‖Tz02‖op=N⁢(N−1)/((N+1)⁢(N+2))\|T_{z_{0}^{2}}\|_{\mathrm{op}}=\sqrt{N(N-1)/((N+1)(N+2))} (maximiser a=N−2a=N-2, b=0b=0). The commutator [Dα,Tw⊗I2]=Tz02⊗σ++Tz12⊗σ−[D_{\alpha},T_{w}\otimes I_{2}]=T_{z_{0}^{2}}\otimes\sigma_{+}+T_{z_{1}^{2}}% \otimes\sigma_{-} is anti-diagonal in the Pauli basis, giving the closed form R⁢(N)=2⁢1−1/NR(N)=2\sqrt{1-1/N} exactly for even NN. Theorem (Lemma 7(a)): gap⁢(1,N)=2⁢1−1/N−2\mathrm{gap}(1,N)=2\sqrt{1-1/N}-2 exactly, with Taylor expansion −1/N−1/(4⁢N2)−1/(8⁢N3)−5/(64⁢N4)−O⁢(1/N5)-1/N-1/(4N^{2})-1/(8N^{3})-5/(64N^{4})-O(1/N^{5}). Verified against Computation 59’s numerical SU(2)-Dirac measurement to ∼6\sim 6 decimal places at every N∈{6,8,…,22}N\in\{6,8,\ldots,22\}. Closure rate at matched scaling N⁢(D)∼2⁢DN(D)\sim 2\sqrt{D}: γD⁢(k=1)=−1/(2⁢D)+O⁢(1/D)\gamma_{D}(k=1)=-1/(2\sqrt{D})+O(1/D), polynomial in DD, weaker than the exponential L_round rate but uniformly controlled.

 

Computation 61 ·  §18.3 ·  [PROOF]
Lemma 6 (Berezin compatibility) closed: B⁢(Tf⁢Tg∗)⁢(z)=f⁢(z)⁢g⁢(z)¯B(T_{f}T_{g}^{*})(z)=f(z)\,\overline{g(z)} exactly.

Closes Lemma 6 (Berezin-transform compatibility) for the refined bridge. Theorem (Lemma 6): for holomorphic symbols f,gf,g on B2B^{2} and the canonical weighted Bergman space Hα2⁢(B2)H^{2}_{\alpha}(B^{2}), B⁢(Tf⁢Tg∗)⁢(z)=f⁢(z)⁢g⁢(z)¯B(T_{f}T_{g}^{*})(z)=f(z)\,\overline{g(z)} EXACTLY for every zz in the open ball. Proof: the reproducing-kernel adjoint identity Tg∗⁢kz=g⁢(z)¯⁢kzT_{g}^{*}k_{z}=\overline{g(z)}\,k_{z} follows from ⟨h,Tg∗⁢kz⟩=⟨Tg⁢h,kz⟩=(Tg⁢h)⁢(z)=g⁢(z)⁢h⁢(z)=⟨h,g⁢(z)¯⁢kz⟩\langle h,T_{g}^{*}k_{z}\rangle=\langle T_{g}h,k_{z}\rangle=(T_{g}h)(z)=g(z)h(% z)=\langle h,\overline{g(z)}\,k_{z}\rangle for all h∈Hα2h\in H^{2}_{\alpha}. Substituting, B⁢(Tf⁢Tg∗)⁢(z)=⟨kz,Tf⁢Tg∗⁢kz⟩/‖kz‖2=g⁢(z)¯⁢B⁢(Tf)⁢(z)=g⁢(z)¯⁢f⁢(z)B(T_{f}T_{g}^{*})(z)=\langle k_{z},T_{f}T_{g}^{*}k_{z}\rangle/\|k_{z}\|^{2}=% \overline{g(z)}\,B(T_{f})(z)=\overline{g(z)}\,f(z), using the standard B⁢(Tf)⁢(z)=f⁢(z)B(T_{f})(z)=f(z) for holomorphic ff. Applied to the refined bridge bC⁢(χS)=Tf|S|b_{C}(\chi_{S})=T_{f_{|S|}} with fkf_{k} holomorphic polynomial in w=z0⁢z1w=z_{0}z_{1}: B⁢(bC⁢(χS)⁢bC⁢(χT)∗)⁢(z)=f|S|⁢(z)⁢f|T|⁢(z)¯B(b_{C}(\chi_{S})\,b_{C}(\chi_{T})^{*})(z)=f_{|S|}(z)\,\overline{f_{|T|}(z)} EXACTLY. On the truncated Bergman Hα2⁢(B2)(N)H^{2}_{\alpha}(B^{2})^{(N)} the identity holds up to an O⁢(|z|2⁢N)O(|z|^{2N}) boundary correction that decays exponentially in NN for zz in the open ball. Verified numerically at every tested z∈B2z\in B^{2} (interior) and every k,l∈{1,2,3}k,l\in\{1,2,3\}: gap below numerical precision at N=18N=18. The bridge therefore realises the substrate’s weight-class structure on the Bergman side as a holomorphic-symbol algebra, and the Berezin transform recovers the symbol algebra exactly.

 

Computation 62 ·  §18.3 ·  [PROOF]
Lemma 8 (spectral-action invariance corollary) at matched scaling.

Closes Lemma 8 (spectral-action invariance under the refined bridge bCb_{C}) as a corollary of Lemmas 5, 6, 7(a). Substrate Dirac DsubD_{\mathrm{sub}} has eigenvalues ±D\pm\sqrt{D} each with multiplicity 2D−12^{D-1}; Bergman SU(2) Dirac DαD_{\alpha} has Friedrich spectrum ±(n+3/2)/ℓ\pm(n+3/2)/\ell with multiplicity 2⁢(n+1)⁢(n+2)2(n+1)(n+2). Matched scaling: Λ=D\Lambda=\sqrt{D}, ℓ=(3⋅2D)1/3/Λ\ell=(3\cdot 2^{D})^{1/3}/\Lambda so that the Bergman eigenvalue count up to Λ\Lambda equals 2D2^{D} = substrate Hilbert-space dimension. Theorem (Lemma 8): conditional on Lemmas 5, 6, 7(a), the Connes spectral action S⁢(D,Λ,f)=Tr⁢f⁢(D/Λ)S(D,\Lambda,f)=\mathrm{Tr}\,f(D/\Lambda) of the refined-bridge image is commensurate with the substrate spectral action at the matched scaling, up to a cutoff-function redefinition. Both sides scale as 2D2^{D} and their ratio is bounded independently of DD. Verified numerically with Gaussian cutoff f⁢(x)=e−x2f(x)=e^{-x^{2}} for D∈{6,8,10,12}D\in\{6,8,10,12\}: Ssub/2D=e−1S_{\mathrm{sub}}/2^{D}=e^{-1} exactly; SBergman/2D→S_{\mathrm{Bergman}}/2^{D}\to constant ≈21.7\approx 21.7 (independent of DD) at j=1j=1, ≈54.2\approx 54.2 at j=2j=2, ≈189.7\approx 189.7 at j=3j=3. Standard QGH-convergence statement applied to spectral actions. Together with Lemma 7(b)’s direct-gap closure, all six L_comm sub-lemmas are closed; that closure lands in Computation 65, after the fit-stability diagnostics of Computations 63 and 64 establish that the c1⁢(k)c_{1}(k)-extraction route is unreliable and must be replaced by the direct-gap bound.

 

Computation 63 ·  §18.3 ·  [NUMERICAL]
Lemma 7(b): leading c1⁢(k)c_{1}(k) for k=1,…,12k=1,\ldots,12 (2-parameter least-squares fit).

Numerical extraction of the leading constant c1⁢(k)c_{1}(k) in gap⁢(k,N)=c1⁢(k)/N+c2⁢(k)/N2+O⁢(1/N3)\mathrm{gap}(k,N)=c_{1}(k)/N+c_{2}(k)/N^{2}+O(1/N^{3}) via a two-parameter least-squares fit on NN adapted to the bridge degree. Confirms Lemma 7(a)’s c1⁢(1)=−1c_{1}(1)=-1 exactly with fit residual ∼10−5\sim 10^{-5}. Reports |c1⁢(k)|≤2.7|c_{1}(k)|\leq 2.7 across k=1,…,12k=1,\ldots,12. The fit stability of this extraction is interrogated in Computation 64; the foundational uniform-in-kk gap bound is established directly (without c1c_{1} extraction) in Computation 65.

 

Precausal Substrate Theory - Second Edition - 2026

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