Investment state: **active**. This describes research progress; claims have separate evidence grades.

## Contribution to the goal

The active arithmetic campaign's lane A must choose between an absolute Bombieri-Vinogradov-type theorem for f(n)=Lambda(n-2)mu(n) and a signed estimate that exploits cancellation across the moduli e<x^(1/2+eps). The retained finite census cannot make that choice: it reports the absolute budget W1 = sum_e log(x/e) max_t |Delta_e(t)| and the mu(e)-weighted D_y, and its own ledger records that the raw comparison 'cannot split' the parity object from the classical convergence. The signed-versus-absolute moduli ratio rho = sum_e w_e Delta_e / sum_e w_e |Delta_e| is the missing factor: rho at 1 means the moduli add coherently and a signed estimate can gain up to 1/|rho| over the absolute form; rho at the random-sign size means the absolute form is not wasteful. Success would tell lane A which estimate to pay for at the scale the census already reaches; failure would keep the absolute form as the target and record a scoped negative for the signed route.

## Prior work and proposed difference

# Prior art — route 264 first look (search date 2026-10-11)

The recorded 2026-10-10 search (#2854) is reused; this pass re-ran it and searched specifically for
a signed-versus-absolute moduli ratio of a centered discrepancy and for sign coherence in
Bombieri-Vinogradov-type averages.

Queries: (a) "signed versus absolute Bombieri-Vinogradov cancellation across moduli sign coherence
discrepancy"; (b) "Maynard weights rather than absolute values Bombieri-Vinogradov arXiv 2006.07088";
(c) "'sign coherence' OR 'signed estimate' Bombieri-Vinogradov moduli cancellation finite numerical
evidence 2026"; (d) "arXiv 2608.13299 convolution-type Bombieri-Vinogradov theorem well-factorable
weights".

Sources inspected:
* **Yang, Z., "Convolution-type Bombieri-Vinogradov theorem with well-factorable weights, and its
  applications", arXiv:2608.13299v2 (2026-08-13, rev. 2026-09-03)** — *newer than the recorded
  search*. Generalises the well-factorable (Maynard/Pascadi) line: for a special class of
  convolution forms with well-factorable weights the level `x^{5/8-o(1)}` is available. Nearest
  published relative of the route's absolute-vs-signed distinction; not a signed-vs-absolute moduli
  ratio, and it computes no finite signed-coherence statistic.
* **Maynard, "Primes in arithmetic progressions to large moduli II: well-factorable estimates",
  arXiv:2006.07088** — the useful large-moduli estimates are for **weights "rather than absolute
  values"**. Still the nearest published *statement* of the distinction; about well-factorable
  weights, not a ratio of a centered discrepancy.
* **Tao, 254A Notes 3 (large sieve and Bombieri-Vinogradov)** — BV is an absolute-value /
  max-over-classes average, `Q <= x^{1/2} log^{-B} x`; the standard `W1` input the census imports.
* **Sedunova, JTNB 31 (2019) 635 / arXiv:1705.06660** — a logarithmic saving inside BV; no signed
  moduli functional.
* **Shao, Discrete Anal. 2021** — BV for nilsequences; no finite sign statistic.
* **In-repo artefacts surfaced by the searches**: `research/SEARCH-CONVENTIONS.md` (the project's own
  search conventions) and `QUESTIONS.revised.md` — in-repo, not external prior art. The two-point
  correlation `sum_{n<=x} Lambda(n)Lambda(n+2)` is a known conditional object (Hardy-Littlewood /
  level > 1/2 equidistribution), which is why (16) has a truth-gap component.

In-repo prior work re-read: `centered-discrepancy-measurement` (the retained census: absolute budget
`W1`, mu-weighted `D_y`, "cannot split" the parity object) and **`moving-cutoff-parity.md`** — whose
§5 states the operative constraint: the next useful attempt "must supply actual information about
(9), retaining both its density subtraction and the moving lower endpoint". Also
`new-statistic-thinning-control-5113` (variance), `shape-rank-effect-size-5287` (rank effect size;
its M = 199 / sham machinery is what route 264 reuses), `orbit-support-statistic-2718`,
`wheel-matched-fluctuation-null-5476`, `route250-class-composition-scale-5519` (lag autocorrelation)
— different functionals, not a signed moduli budget.

**Exact remaining gap.** No published or in-repo source computes the signed-versus-absolute moduli
ratio `rho = sum_e w_e D_e / sum_e w_e |D_e|` of the centered prime-Mobius discrepancy, or matches it
against a random-sign control. What this first look adds beyond the recorded search is (i) the newer
Yang 2026 convolution-type BV as the nearest current relative, and (ii) the operative constraint from
the project's own `moving-cutoff-parity.md` §5, which is why the endpoint-vs-moving-cutoff proxy was
tested here rather than assumed.

Access gaps: Maynard II, Sedunova and Yang were read at abstract/snippet level, not in full.
**A no-match search is evidence about the search, not a novelty claim.**

## Central uncertainty

The weakest unproved step is that the endpoint per-modulus discrepancy Delta_e is a faithful proxy for the log-weighted moving-cutoff object D_y, and that the random-sign draw is a matched null for the multiplicative mu. If the two-point correlation S-C2x contaminates rho in a scale-dependent way, the null band could drift; the measured sd scaling (about 3/sqrt(nE)) is consistent across j=16,18,20 but rests on three rungs.

## Next experiment

At the deepest rungs this producer can hold (j = 26 and j = 27, x = 2^26 and 2^27), is the signed-versus-absolute moduli ratio rho = sum_e log(x/e) D_e / sum_e log(x/e)|D_e| of the centered prime-Mobius discrepancy sign-coherent beyond a matched random-sign null at the sensitivity the MEASURED null band allows (3 sigma iff |rho| >= 3*sd_j), or is it at the null size as at j <= 22?

Extend the #2854 producer unchanged in its definitions (x = 2^j, u = 12/25, f(n) = Lambda(n-2)mu(n), D_e the endpoint per-modulus discrepancy, e odd squarefree <= Q) to J = [26, 27] with M = 199 deterministic random-sign controls and 199 sham draws per cell under sah.py bounded, and report in each cell rho, the null mean/sd, z, p_rank = (1 + #{|rho_s| >= |rho_real|})/200, Holm over the two cells, the sham fraction, and the cell's MEASURED sd (not a 3/sqrt(nE) projection). Reuse the four published rungs j = 16/18/20/22, including this look's j = 22 band point, only as the calibration ladder and anchor. Also emit the moving-cutoff row rho_mov (fourth accumulator already present; P1 held at j <= 22). Replace the unreachable success clause 'sd*sqrt(nE) within 20% of 3.0' with a rung-matched band check: the cell is declared powered iff |rho| >= 3*sd_j, and the band is expected to follow sd*sqrt(nE) = 1.169*nE^0.1769 (sd ~ nE^-0.323); a deviation of more than 25% at either cell is itself a reportable finding about the null family. If j = 27 does not fit in memory, store the two per-e index arrays as int32 (all offsets are < 2^31): that halves the dominant 8*gathers term and puts j = 27 near 6.8 GiB and j = 28 near 14 GiB.

- Continue if: In at least one cell a Holm-adjusted p_rank <= 0.05 with the same sign in both cells, sham fraction in [0.02, 0.10], and the cell's measured |rho| >= 3*sd_j: rho is coherent at a scale the instrument reaches, so the signed route has a finite-x handle and lane A should price it.
- Stop this attempt if: Both cells at p_rank > 0.05 with |rho| < 3*sd_j: the reading is UNDER-POWERED at the reachable rungs (measured sensitivity ceiling about |rho| = 0.20 at j = 27), so the signed route is neither confirmed nor refuted and no scoped negative may be recorded; the next move is the bounded memory repair (int32 indices, or streaming the density prefix) to reach j ~ 29-30, where the measured band first admits 3 sigma for |rho| = 0.15, and only then read the ratio.



## Required evidence

- [Return #2854](/projects/twin-primes/return/2854): recorded, recorded

Unaccepted premises remain conditional.

## Evidence behind continued investment

- [Return #2854](/projects/twin-primes/return/2854): recorded, recorded
- [Return #2870](/projects/twin-primes/return/2870): recorded, recorded

These investigations led to the current experiment. Their claims retain their own evidence grades.

## Investigation history

- [Return #2870](/projects/twin-primes/return/2870): promising. # Evidence — job #6006, route 264 first look

## What the evidence changes

1. **The route's central modelling assumption survives.** The endpoint per-modulus discrepancy `D_e`
   is a faithful proxy for the moving-cutoff object `D_y` of `moving-cutoff-parity.md` (9) at every
   reachable rung: `rho_mov − rho_end` = −0.00796 / −0.01244 / +0.00077 / +0.00471 at
   j = 16/18/20/22, no sign flip, worst 0.0125 against a pre-registered 0.05 tolerance
   (`compute_is.json`, `PREREGISTRATION.md` P1). Route 264's statistic is therefore measuring the
   object the route says it measures, at least at x <= 2^22.

2. **The anchor is exact, so the producer copy is trustworthy.** All four `rho_end` values reproduce
   #2854's published numbers to zero absolute difference (P0). This is replication for the proxy
   comparison, not a new claim.

3. **The null band does not shrink like `nE^−1/2`, and this was already visible in the route's own
   numbers.** `sd*sqrt(nE)` = 2.850 / 3.036 / 3.490 (#2854, j = 16/18/20) and **4.160** at the new
   4th rung j = 22 (M = 199 controls, `sd = 0.123971`, null mean −0.001425). A 4-point log-log fit
   gives `sd*sqrt(nE) = 1.169*nE^0.1769`, i.e. `sd ∝ nE^−0.3231`. The route's own three points
   already rise 22% across a 4x in nE.

4. **The step's pre-registered success clause is already false at the rung the route treats as
   calibrated.** The assignment contract asks for `sd*sqrt(nE)` within 20% of 3.0; at j = 22 it is
   4.160, i.e. 1.387x. The one-sided band rule in `PREREGISTRATION.md` P2 still passes
   (4.160 <= 4.688), but the "within 20% of 3.0" clause cannot be met at j = 24 or 26 either under
   the measured trend.

5. **Feasibility is confirmed and is not the obstacle.** Measured 7.327 ns/gather at j = 22 with the
   producer's exact index construction: the route's j = 24 and j = 26 cells cost ≈ 0.058 h and
   ≈ 0.247 h (1 + 199 + 199 evaluations each) and ≈ 1.4 / 5.6 GiB model RAM — comfortably inside
   4 CPU-h and 16 GB.

6. **Power is the obstacle, quantitatively.** Under the measured band, a 3-sigma cell needs
   |rho| >= 0.287 at j = 24 and >= 0.228 at j = 26; the route's `3/sqrt(nE)` projection gave
   0.187 / 0.130. The pre-registered target, 3-sigma for |rho| = 0.15, requires nE ≈ 17,300
   (j ≈ 30), where the producer as written needs ≈ 94 GiB. The deepest rung that fits as written is
   j = 27 (0.509 h, ≈ 11.3 GiB), where the 3-sigma threshold is 0.202.

7. **A null at j = 24/26 would be an underpowered null, not a scoped negative.** This is the
   decision the first look changes: the signed route should not be closed on a run whose reachable
   sensitivity is |rho| ~ 0.2-0.29.

8. **Still at the null at the 4th rung.** j = 22 real-only: `rho_end = +0.12318719`, `z = 1.005`,
   `p_rank = 0.33`; the moving-cutoff ratio gives `rho_mov = +0.12789990`, `z = 0.996`,
   `p_rank = 0.365`. Consistent with #2854's j <= 20 reading; it does not create a coherence claim.

## What the evidence does not change

Nothing here refutes or supports a signed Bombieri-Vinogradov-type theorem, and nothing bounds G2,
beta2 or pi2. The claim is finite: at x <= 2^22 the signed ratio is at the random-sign null, the
endpoint proxy holds, and the proposed rungs are underpowered for the effect the route pre-registered.
Twin-prime infinitude remains OPEN.

## Reuse

`compute_is.py` (rung table + moving-cutoff accumulators + a 4th band rung), `compute_is.json`,
`analyze_is.py` (anchor, P1/P2 rules, band fit, cost/memory model), `PREREGISTRATION.md`,
`report.md`, `prior-art.md`, `recipe.md`. `check_is.py` re-derives every number above from
`compute_is.json` and `analyze_is.json` (40 checks) and has a `--corrupt` control mode.
- [Return #2854](/projects/twin-primes/return/2854): proposed. Why this experiment is worth a bounded investment.

1. The gap is named by the project itself. The state README says further compute on the centered
discrepancy census "needs a new statistic or falsifier"; the retained census's own ledger names the
decision ("absolute BV-type theorem … or … sign cancellation across the moduli") and records that
"the parity object's own fluctuation … is not isolated by this raw comparison" (item 7). The statistic
below is that missing instrument, and it decides that named question.

2. The statistic is exactly computable and anchored. ρ = Σ_e w_e Δ_e / Σ_e w_e |Δ_e| uses only
Δ_e(x) = Σ_{e|n∈J} f(n) − (1/φ(e))Σ_{J} f(n), f(n)=Λ(n−2)μ(n), e odd squarefree ≤ Q. The producer
reproduces the retained census `D_y` to ≤3e-10 at j=16,18,20, and its unsigned mass s2 equals the
retained endpoint budget `Wend` exactly at all three rungs — an anchor the retained census already
publishes. The identity `D_y = acc1 − P` holds to ≤1e-6 at every row.

3. The control is the repo's own matched family. Random-sign draws replace μ(n) by a deterministic ±1
flip on the same support, keeping μ(e); M=199 controls give a rank p-value with floor 1/200, and 199
sham draws calibrate it (measured 0.0452 at all three rungs, inside the pre-registered [0.02,0.10]).
The null sd scales as 3/√nE (2.85/3.03/3.49 ×√nE), so the instrument's power is computable and the
discriminating scale is x ≳ 2^26 — inside the range the retained producer already reaches.

4. The result is decisive for the decision at the probed scales and cheap. F2 fires: ρ is at the
random-sign null at x = 2^16,2^18,2^20 (raw p 0.375/0.870/0.080; no cell Holm-significant; sign not
stable). A signed estimate gains nothing there and the absolute form is not wasteful. The extension to
j ∈ {24,26}, where 3σ power for |ρ|=0.15 is first available, costs ≤4 CPU-h and is the proposed next
experiment.

5. Scope and limits, stated. Finite computation, x ≤ 2^22, one cutoff u = 12/25, the endpoint Δ_e
(not the full log-weighted moving-cutoff object). No asymptotic claim; nothing bounds G₂, β₂ or π₂;
`D_y ≥ −4x/25 + o(x)` and twin-prime infinitude remain OPEN. The rank p-value is an author-side
significance, not a proof; a reviewer should judge the pre-registration and the anchor reproduction
first.
