Self-as-an-End

ZFCρ Paper 57: The Screened Spectral Bound and the Block Mean Target

DOI: 10.5281/zenodo.19469014  ·  CC BY 4.0

Abstract

Paper 56 promoted the direct weighted spectral ratio R_j^{wt} = I_j(0)/(j·D_j) to the front-door conjecture for the mean spectral target, with Papers 53–55 reinterpreted as the mechanism/proof program. This paper completes the DSF branch by proving a conditional theorem that connects the screened long-memory framework of Papers 53–54 to the spectral ratio.

Theorem 57.1 (Screened Spectral Bound). If the prime-index autocorrelation satisfies power-law buildup (|ρ(k)| ≤ A·k^{-α} for k ≤ n_cross, α > 0), post-crossover screening (cumulative negative), and linear crossover scale (n_cross ≤ c·j), then the variance ratio Ψ_j ≤ 1 + C·j^{1-α}, giving E[R_j^{wt}] = O(j^{-α}) → 0.

Extended data at 7 dyadic blocks (j = 14, 17, 20, 23, 26, 29, 32) confirms: R_wt ∈ [2.7, 25.3] bounded, z/√j shows a crossover peak at j ≈ 23 then declines, and z²/j^{0.65} ∈ [9.0, 72.0] is bounded with the same crossover — all consistent with z² = O(j^{0.65}) from α ≈ 0.35. The oscillation (single-realization fluctuation) is larger than the trend, but the upper envelope is controlled.

Under the three conjectural inputs (supported by Papers 53–56), Theorem 57.1 conditionally closes the mean spectral target for the DSF branch. The remaining gaps for H' are BL_α verification, mean-to-deterministic, and L²-to-pathwise upgrades.

Keywords: integer complexity, spectral target, screened long memory, block mean, DSF, H' conjecture


§1. Introduction

1.1 From Paper 56 to Paper 57

Paper 56 made two contributions. Part I proved the Affine Trough Theorem, filling Paper 55's signed gap (positive-tail bound does not control zero-crossing). Part II measured the exact weighted spectral ratio R_j^{wt} = I_j(0)/(j·D_j) on the Paper 51/53 observable and found it bounded at j = 20–32. This led to a strategic pivot: Conjecture 56.2 (R_j^{wt} = O(1)) became the front-door conjecture, and Papers 53–55 were reassigned as the mechanism/proof program.

Paper 56 also identified the block mean theorem (z_j = O(√j)) as the cleanest proof target, noting that B_j^{wt} is 84–99% dominated by the block mean of η.

Paper 57 proves the conditional theorem that links the screened covariance framework (Papers 53–54) to this block mean target, and extends the empirical verification to 7 j-values.

1.2 The logical arc

Paper 53: screened long memory framework, n_cross/j ≈ 30
Paper 54: power-law autocorrelation C(k) ~ k^{-α}, α ≈ 0.35
Paper 55: damped oscillation, r ≈ 0.80, positive-tail bound
Paper 56: sign-change theorem + direct spectral ratio as front-door
Paper 57: screened covariance → E[z²] = O(j^{1-α}) → E[R_wt] → 0

Each earlier paper contributes a named conjectural input to Theorem 57.1.


§2. Framework

2.1 Notation

Primes p in dyadic block I_j = [2^j, 2^{j+1}), indexed as p_1 < p_2 < ... < p_{m_j}.

Detrended residual: η(p) = ρ_E(p) − λ ln p − μ_{p mod 12} (Paper 55).

Weighted block sum: B_j^{wt} = Σ_{r=1}^{m_j} η(p_r)/p_r.

Spectral quantities: I_j(0) = (B_j^{wt})², D_j = Σ (η(p_r)/p_r)².

Spectral ratio: R_j^{wt} = I_j(0)/(j · D_j).

Prime-index autocorrelation: C_j(k) = Cov(η(p_r), η(p_{r+k})), ρ_j(k) = C_j(k)/σ².

Variance ratio: Ψ_j = Var(Σ η_r) / (m_j · σ²) = 1 + 2·Σ_{k=1}^{m_j-1} (1−k/m_j)·ρ_j(k).

2.2 Proposition (Weight Equivalence)

Proposition 2.1. For primes in I_j = [2^j, 2^{j+1}):

(1/4) · Ψ_j ≤ E[z_j²] ≤ 4 · Ψ_j, (2.1)

where z_j = B_j^{wt} / √(σ² · Σ 1/p²) is the standardized weighted block sum.

Proof. Var(B_j^{wt}) = Σ_{r,s} C_j(|r−s|)/(p_r·p_s). Since all p_r ∈ [2^j, 2^{j+1}]:

1/p_r·p_s ∈ [1/2^{2(j+1)}, 1/2^{2j}].

Therefore Var(B_j^{wt}) ∈ [V_j/4·2^{2j}, V_j/2^{2j}], where V_j = Σ_{r,s} C_j(|r−s|) = m_j·σ²·Ψ_j.

Similarly σ²·Σ 1/p² ∈ [m_j·σ²/4·2^{2j}, m_j·σ²/2^{2j}].

Dividing: E[z²] = Var(B_wt)/(σ²·Σ 1/p²) ∈ [Ψ_j/4, 4·Ψ_j]. □

Remark. The factor-of-4 bound is crude but sufficient: it preserves the polynomial scaling O(j^{1-α}) while only affecting the constant. In practice, the dominant covariance contributions come from small lags |r−s| where p_r ≈ p_s, making the effective factor much closer to 1.


§3. The Screened Spectral Bound

3.1 Theorem 57.1

Theorem 57.1 (Screened Spectral Bound). Assume:

(A) Power-law buildup. There exist A > 0 and 0 < α < 1 such that for all k ≤ n_cross(j):

ρ_j(k) ≤ A · k^{-α}.

(B) Post-crossover screening. The cumulative post-crossover covariance is nonpositive:

Σ_{k=n_cross+1}^{m_j-1} (1 − k/m_j) · ρ_j(k) ≤ 0.

(C) Linear crossover scale. There exists c > 0 such that n_cross(j) ≤ c · j for all j.

Then the variance ratio satisfies

Ψ_j ≤ 1 + C₁ · j^{1-α}, (3.1)

where C₁ = 2A · c^{1-α} / (1−α).

3.2 Proof

Split Ψ_j at the crossover:

Ψ_j = 1 + 2·[Σ_{k=1}^{n_cross} + Σ_{k=n_cross+1}^{m_j-1}] (1−k/m_j)·ρ_j(k).

Buildup term. For k ≤ n_cross ≤ cj, we have k/m_j ≤ cj/(2^j/j) = cj²/2^j → 0, so (1−k/m_j) ≤ 1. By assumption (A):

Σ_{k=1}^{n_cross} (1−k/m_j)·|ρ_j(k)| ≤ Σ_{k=1}^{cj} A·k^{-α} ≤ A·∫_0^{cj} x^{-α} dx = A·(cj)^{1-α}/(1-α).

Screening term. By assumption (B): Σ_{k>n_cross} (1−k/m_j)·ρ_j(k) ≤ 0.

Combining:

Ψ_j ≤ 1 + 2A·(cj)^{1-α}/(1−α) + 0 = 1 + C₁·j^{1-α}. □

3.3 Corollary (Spectral ratio decay)

Corollary 57.2. Under Theorem 57.1, the weight equivalence (Proposition 2.1), and the second-moment hypothesis

(D) D_j = (1 + o(1)) · σ² · Σ_{p ∈ I_j} 1/p²,

we have:

E[R_j^{wt}] = E[(B_j^{wt})²] / (j · D_j) ≤ 4Ψ_j / (j · (1+o(1))) = O(j^{-α}). (3.2)

For α > 0: E[R_j^{wt}] → 0 as j → ∞.

The mean spectral target E[I_j(0)] ≤ C·j·D_j holds for all sufficiently large j. □

Remark on hypothesis (D). This is verified empirically to high precision: D_wt actual / (E[η²]·Σ 1/p²) = 1.000 ± 0.007 across all 7 tested blocks (§4.4). Hypothesis (D) says that the weighted second moment has no anomalous structure beyond what the marginal variance σ² and the 1/p² weights predict. This is a much weaker condition than any of the covariance assumptions (A)–(C), since it only concerns the diagonal (k=0) term.

Remark. With α ≈ 0.35 (Paper 54): E[R_wt] = O(j^{-0.35}). At j = 32: j^{-0.35} ≈ 0.29. The actual R_wt = 2.7 is larger than this bound, which is expected: R_wt is a single realization, while the bound controls the expectation. The gap between E[R_wt] and the actual R_wt is the mean-to-deterministic upgrade (Paper 52, §8).


§4. Extended Data

4.1 Seven-block spectral ratio

j m_j R_wt z √j z/√j j^{0.65} z²/j^{0.65}
14 1,612 8.7 11.4 3.74 3.06 5.6 23.4
17 10,749 15.9 16.7 4.12 4.04 6.4 43.5
20 73,586 22.0 21.0 4.47 4.70 7.2 61.0
23 513,708 25.3 24.1 4.80 5.03 8.1 72.0
26 3,645,744 4.2 10.5 5.10 2.05 8.9 12.4
29 26,207,278 8.9 16.0 5.39 2.97 9.7 26.5
32 190,335,585 2.7 9.3 5.66 1.64 9.5 9.0

R_wt is bounded (2.7–25.3) across all 7 tested blocks, with no upward trend.

4.2 The z/√j crossover

z/√j shows a structured pattern: rising from 3.06 (j=14) to a peak of 5.03 (j=23), then declining to 1.64 (j=32).

This crossover matches the screened long-memory picture:

  • Small j (14–23): IC trees are shallow, screening is weak. Correlations build up, z/√j increases.
  • Large j (26–32): IC trees are deep, screening is strong. Multiplicative resets dominate, z/√j decreases.

The transition at j ≈ 23 is consistent with Paper 53's observation that α(j) decreases with j (heavier tails at larger j) while screening depth increases proportionally.

Phase-transition interpretation. The crossover has a precise arithmetic origin. In block [2^j, 2^{j+1}], the typical integer n has Ω(n) ~ ln ln n ≈ ln j prime factors. At j = 23: ln 23 ≈ 3.14, which falls in the middle of the phase-transition window [2.75, 4.01] identified in SAE Physics Paper VI. Below j ≈ 20 (ln j < 3, pre-window), multiplicative paths are a minority and screening has not established; correlations accumulate freely and z/√j rises. At j ≈ 23 (ln j ≈ 3.1, mid-window), multiplicative paths have just become the majority but screening is still weak — maximum accumulation before screening takes hold. Above j ≈ 25 (ln j > 3.2, post-window), screening is fully established, each cycle dissipates η ≈ 20%, and z/√j declines. The z/√j crossover is therefore the spectral projection of the phase transition — the sixth independent indicator of the transition window, and the first purely spectral one.

4.3 Mean dominance

j Mean part % Fluct part %
14 96.8% 3.2%
17 99.1% 0.9%
20 98.6% 1.4%
23 94.7% 5.3%
26 84.2% 15.8%
29 (111.9%)* 11.9%
32 90.4% 9.6%

(*At j=29, mean and fluctuation parts have opposite signs.)

Mean dominance is consistent across all 7 tested blocks. The fluctuation part Φ_j is at iid scale (|Φ_j|/√(σ²·Σ 1/p²) = 0.29–1.91), confirming that the screened long-memory mechanism keeps correlated fluctuations controlled.

4.4 Second moment verification

D_wt actual / D_wt predicted (= E[η²]·Σ 1/p²) = 1.000 ± 0.007 across all 7 blocks. No anomalous second-moment structure.


§5. Conjectural Inputs

The three inputs to Theorem 57.1 are empirical laws with mechanism explanations from the preceding papers.

5.1 Conjecture 57.A (Power-law buildup)

Within block I_j, the normalized prime-index autocorrelation satisfies |ρ_j(k)| ≤ A·k^{-α} for k ≤ n_cross(j), with A > 0 and 0 < α < 1 uniform in j.

Evidence. Paper 54 established C(k) ~ k^{-α} with α ≈ 0.286 (global fit) to α ≈ 0.35–0.40 (within-block). The power law arises from recursive ancestor inheritance in the DP factorization tree.

5.2 Conjecture 57.B (Post-crossover screening)

The Abel-weighted post-crossover covariance is nonpositive:

Σ_{k > n_cross}^{m_j-1} (1−k/m_j)·ρ_j(k) ≤ 0.

This is the genuinely new prime-level conjectural input of this paper. It is formulated on prime-index autocorrelation ρ_j(k), not on the coarse-block covariance G_j(M) studied in Papers 53–56.

Motivation from Papers 53–56 (not inheritance). Papers 53–56 established screening at the coarse-block level: G_j(M) crosses zero (Paper 56), the post-peak profile is a damped oscillation with r ≈ 0.80 (Paper 55), and the positive tail mass is bounded (Paper 55 Thm 55.3). These coarse-block results strongly motivate 57.B, but they do not directly imply it: the passage from coarse-block sign changes to prime-index Abel-weighted covariance involves additional averaging structure. Conjecture 57.B asserts that the screening mechanism observed at coarse scale persists at the prime-index level with sufficient strength to make the cumulative tail nonpositive.

5.3 Conjecture 57.C (Linear crossover)

n_cross(j) ≤ c·j for some constant c > 0 uniform in j.

Evidence. Paper 53 measured n_cross/j ≈ 27–33, stable across j = 26–32. The crossover scale is proportional to IC tree depth (~j), with proportionality constant ≈ 30.

5.4 Hypothesis (D) (Second-moment regularity)

D_j = (1 + o(1)) · σ² · Σ_{p ∈ I_j} 1/p².

This asserts that the weighted second moment has no anomalous structure beyond marginal variance × weight sum. It is a much weaker condition than (A)–(C), concerning only the diagonal (k=0) term.

Evidence. Verified empirically: D_wt actual / (E[η²]·Σ 1/p²) = 1.000 ± 0.007 across all 7 tested blocks.


§6. Conditional Closure of the DSF Branch

6.1 The complete chain

Under Conjectures 57.A + 57.B + 57.C + Hypothesis (D):

Theorem 57.1: Ψ_j ≤ 1 + C·j^{1-α}
    → Proposition 2.1: E[z²] ≤ 4·Ψ_j = O(j^{1-α})
        → Hypothesis (D): D_j ≈ σ²·Σ(1/p²)
            → Corollary 57.2: E[R_wt] = O(j^{-α}) → 0
                → E[I_j(0)] ≤ C·j·D_j (mean spectral target)
                    → mean-DSF_α (Paper 51)

This conditionally closes the mean spectral target for the DSF branch. The three conjectural inputs distill the empirical discoveries of Papers 53–54 into precise, testable mathematical statements.

6.2 Connection to Paper 56's Conjecture 56.2

Conjecture 56.2 stated R_j^{wt} = O(1). Corollary 57.2 gives the stronger E[R_wt] = O(j^{-α}) → 0. Conjecture 56.2 is therefore a consequence of Conjectures 57.A–C (at the expectation level).

The empirical data is consistent with both: R_wt is bounded at all tested blocks, and z/√j shows a declining trend for j ≥ 23.

6.3 The hierarchy of Papers 53–57

Paper Role in H' program
53 Framework: screened long memory, coarse covariance, n_cross/j ≈ 30
54 Input: power-law autocorrelation (→ Conj 57.A)
55 Input: damped oscillation, positive-tail bound (→ Conj 57.B)
56 Pivot: direct spectral ratio as front-door, sign-change theorem
57 Conditional bridge: screened spectral bound → E[R_wt] → 0

§7. The Block Mean as Proof Target

7.1 Proposition (Mean–Fluctuation Decomposition)

Proposition 7.1. (= Paper 56, Proposition 4.1.) Let η̄_j = (1/m_j) Σ η(p) be the block mean. Then

B_j^{wt} = η̄_j · S_j + Φ_j,

where S_j = Σ 1/p and Φ_j = Σ (η(p)−η̄_j)/p is the centered fluctuation.

Under the empirically observed mean-dominated regime (84–99%, §4.3), R_wt is primarily controlled by the block mean η̄_j. The condition z_j = O(√j) reduces approximately to

η̄_j ² · m_j / σ² = O(j).

Since m_j ~ 2^j/j: |η̄_j| = O(j/√(2^j)).

7.2 Why the block mean decays

Theorem 57.1, at the expectation level, supports the conclusion that the block mean decays: the screened covariance structure ensures that the block sum B_j (and hence the block mean η̄_j) grows at most as √(j^{1-α}) faster than CLT rate. The extra √j over naive CLT comes from the power-law correlations up to the crossover scale; but the 1/j in the spectral ratio absorbs this excess.

The crossover peak at j ≈ 23 (§4.2) corresponds to the transition from correlation-dominated to screening-dominated behavior: below j ≈ 23, the power-law buildup increases z/√j; above j ≈ 23, screening wins and z/√j declines.


§8. Remaining Gaps for H'

8.1 What Theorem 57.1 closes

The DSF branch (mean spectral target → mean-DSF_α), conditional on Conjectures 57.A–C.

8.2 What remains

Gap 1: Mean to deterministic. Theorem 57.1 bounds E[R_wt], not the actual R_wt for the single deterministic realization. To pass from E[I_j(0)] ≤ C·j·D_j to the actual I_j(0) ≤ C·j·D_j requires a concentration argument or a stronger deterministic bound. This is Paper 52's Upgrade 1.

Gap 2: BL_α. Paper 51 established that the spectral target I_j(0) ≤ C·j·D_j implies DSF_α but not automatically BL_α. The BL branch requires a separate verification (spectral continuity or direct localization argument).

Gap 3: L² to pathwise. Paper 52's Upgrade 2. Passing from L² bounds to pathwise (almost-sure) statements.

8.3 Updated H' distance

Papers 53–57: DSF branch (mean, conditional) ✓

Remaining:
    Gap 1: mean → deterministic (concentration)
    Gap 2: BL_α (separate branch)
    Gap 3: L² → pathwise
        → DSF_α + BL_α → H'

§9. AI Contributions

Claude (子路, experimental partner): All computational experiments. paper57_spectral.c (extended weighted spectral ratio, j=14–32). Variance decomposition algebra and weight equivalence proof (Proposition 2.1). Theorem 57.1 proof construction. Block mean analysis: z/√j crossover discovery. Working notes v1.

ChatGPT (公西华, structural gatekeeper): Strategic direction for Paper 57. Identified "conditional theorem linking screened covariance to block mean" as the requirement for standalone paper (vs note). Gave explicit theorem target: E[z²] ≤ 1 + j^γ with γ < 1. Confirmed 7-point data strengthens block-mean pivot. Specified claim hierarchy (what to say, what not to say). Positioned Paper 57 as DSF branch capstone.

Gemini (子夏): Physical intuition for Papers 55–56 mechanisms feeding into Conjectures 57.A–B. Coulomb friction / screening floor interpretation of β.

Grok (子贡): Numerical predictions for Paper 55–56 oscillation parameters.


§10. Data and Methods

All experiments used the rho_1e10.bin dataset (ρ_E values for n = 0 to 10^10, int16 binary format).

paper57_spectral.c: Single-pass computation of weighted (x = η/p) and unweighted (η) spectral ratios at j = 14, 17, 20, 23, 26, 29, 32. Accumulates B_wt, D_wt, B_uw, D_uw, plus mean/fluctuation decomposition. Verified D_wt = E[η²]·Σ(1/p²) to 0.7% and z²/j ≈ R_wt to 4+ digits at all blocks.


References

  • [P51] Qin, H. ZFCρ Paper 51: Spectral target and DSF. DOI: (series)
  • [P52] Qin, H. ZFCρ Paper 52: Mean-reversion and two upgrades. DOI: (series)
  • [P53] Qin, H. ZFCρ Paper 53 v2: Screening Return Theorem. DOI: 10.5281/zenodo.19415440
  • [P54] Qin, H. ZFCρ Paper 54: Recursive ancestor inheritance. DOI: 10.5281/zenodo.19426094
  • [P55] Qin, H. ZFCρ Paper 55: Damped oscillation, 70/30 law, positive-tail theorem. DOI: 10.5281/zenodo.19447349
  • [P56] Qin, H. ZFCρ Paper 56: Affine trough theorem and spectral closure equation. DOI: 10.5281/zenodo.19464605
  • [Thermo] Qin, H. SAE Thermodynamic interface paper. DOI: 10.5281/zenodo.19310282