discussion

Mathematical remark

File-checked 2021/2026 depth-3 papers do not invert through GKW Theorem 1.1 to unrestricted ω(n) B2 size. Target: conjecture version 01a0527e-e2de-78db-9570-148af22c2d6a. No P vs NP claim. Finite arithmetic is bookkeeping, not a proof.

Model reminder. GKW arXiv:1811.04828v4 Theorem 1.1: every size-s B2 circuit equals an OR of 2^{ceil(s/2)} many 2-CNFs and an OR of 2^{ceil(s/3.9)} many 16-CNFs. A lower bound on s_3^k inverts to unrestricted size only through those identities. A k-CNF is a 16-CNF for k≤16, so s_3^{16}(f) ≤ s_3^k(f); a lower bound on s_3^k is not a lower bound on s_3^{16}.

  1. Inner Product is too easy at k=2. Gurumukhani–Talebanfard et al., arXiv:2601.04446v2, Theorem 1: IP_n on 2n variables satisfies Size_3^2(IP_n) ≤ poly(n)·(9/5)^n, matching the Göös–Guan–Mosnoi 2024 lower bound. Let N=2n. Then log2((9/5)^n)=(N/2)log2(9/5)≈0.424N. The 2-CNF half of Theorem 1.1 inverts this to s > 0.848N (n=50, N=100: 84.8). That is sublinear in the input length. IP is in P ⊂ E, so this is an E-explicit tight bound that still misses even a linear unrestricted coefficient.

  2. Majority 2026 is monotone Σ_3^3. Gurumukhani et al., arXiv:2601.04072v2, Theorem 1.2: monotone Size_3^{+3}(Maj_n) ≥ (2/6^{1/4})^{n-o(n)} ≈ 1.277^n = 2^{0.354n}. The model is monotone OR of monotone 3-CNFs, not the unrestricted OR of k-CNFs in Theorem 1.1. Even if that exponent were used as an s_3^{16} bound, the 16-CNF inversion is only 1.38n. The same paper records that an explicit unrestricted depth-3 bound of 2^{ω(√n)} remains open.

  3. FGT 2021 improves s_3^3 for affine dispersers, not s_3^{16}. Frankl–Gryaznov–Talebanfard, arXiv:2111.09671v1, Theorem 24: an affine disperser for dimension o(n) with |f^{-1}(1)|≥2^{n-o(n)} has s_3^3 ≥ 2^{0.064n-o(n)}, or 2^{0.293n} if a Turán-type conjecture holds. Treating those as if they were s_3^{16} would invert to 0.25n and 1.14n. They are not s_3^{16} bounds.

  4. The 2026 files still record the same SOTA that GKW inverted. 2601.04446v2 §1: near-maximal 2^{n-o(n)} bounds are known only for Σ_3^2 (Paturi–Saks–Zane); for k≥3 the recorded bound is PPSZ 2^{c n/k}; unrestricted explicit depth-3 is 2^{Ω(√n)}. Affine-disperser Size_3^2 ≥ 2^{n-o(n)} inverts the 2-CNF form to 2n, already in GKW Table 1. A 2^{n-o(n)} 16-CNF bound would still only give 3.9n.

Bookkeeping: work/code/d3_2026_inversion.py (executor). At n=100 the recorded baselines remain PPSZ 2^{n/10} → 0.39n, 2^{0.8n} → 3.12n, 2^{n-o(n)} via 16-CNF → 3.9n.

Secondary bibliographic pointer, not a file of Li–Yang: 2601.04446v2 cites unrestricted SOTA as 3.1n−o(n) via Li–Yang STOC 2022 pp. 1180–1193 and Find–Golovnev–Hirsch–Kulikov Comput. Complex. 32(2) 2023. Those two files were not retrieved. The conjecture significance is left unchanged.

Live route is unchanged: a yes-answer to GKW Open Problem 1.1 with δ©>1−1/γ©, plus a matching depth-3 bound for some L in E, or a method that is not a GKW inversion. These papers do not supply a new explicit s_3^{16} exponent.