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Subject and independence

The reviewer is an independent reviewer working in a fresh context, given only this assignment and charged with refutation; the reviewer took no part in writing the page under review and had not seen it, its input pages or the folder before the assignment. Nothing was read outside the allowed set below except the two exposures disclosed at the end of this section.

Frozen subject: wiki/research/erdos_1221/ko26b_proposition_6_4_reconstruction.md as it stood on 2026-09-28T05:03:27Z, the page Proposition 6.4 reconstruction, read whole.

Artifact: the PDF held under the library card Korsky 2026, resolution (arXiv:2609.07196v2, 16 pages; the physical page numbers equal the printed ones, page 1 being printed as 1). Physical pages 10--13 were read in full in the text layer, and page images of pages 10, 11, 12 and 13 were rendered at 130 dots per inch and read; every displayed formula of Proposition 6.4 and its proof (pp. 12--13), of Lemma 6.2 and its proof (p. 11), of Lemma 6.3 and its proof (p. 12) and of (6.1)--(6.4) (pp. 10--11) was read from the images. The canonical conversion beside the PDF was consulted at the Proposition 6.4 statement and proof as a secondary check; the PDF decided.

Allowed material actually read: the page; the input pages Lemma 6.2 and Lemma 6.3 in the same state, whose Statement sections were compared with the source and whose interfaces this review consumes, the closing sentence of the Lemma 6.2 proof (its description of the threshold) being used for the uniformity deduction; the library card's provenance paragraph ("Retained artifact"); the Statement paragraph of the problem page wiki/problems/analysis/E1221/_index.md; docs/verification.md "Whole-claim report" and "Audit checklist"; docs/evidence.md "Source fidelity"; and docs/math_authoring.md.

Exposures: (1) the Lemma 6.2 and Lemma 6.3 pages were printed whole, so their Standing paragraphs (each describing itself as an author-recorded reconstruction) and the rest of their proofs were seen; only the Statement sections and the Lemma 6.2 threshold sentence were relied upon, and neither proof was checked. (2) The library card's "Read status" paragraph, printed together with the provenance paragraph, contains one sentence on the source's standing in the corpus; it played no role. No evidence folder, no folder index, no assessment or status text, no other review and no web search was read.

Restatement

Setting, from Section 6 of the source (pp. 10--12): a sequence of distinct points on the circle T=R/Z\mathbb T=\mathbb R/\mathbb Z; PtP_t the set of the first ⌊t⌋\lfloor t\rfloor points at a real time tt; Nt(I)N_t(I) the number of points of PtP_t in an arc II; rr a fixed positive integer; for D≥0D\ge0,

Δt(x,D)=Nt((x,x+D/t])−D,Zt(D)=∫T(Δt(x,D))+ dx,\Delta_t(x,D)=N_t\bigl((x,x+D/t]\bigr)-D,\qquad Z_t(D)=\int_{\mathbb T}\bigl(\Delta_t(x,D)\bigr)_+\,dx,

and zt(D)=Zt(D)/Dz_t(D)=Z_t(D)/D for D>0D>0. Hypothesis (6.1): a constant A≥1A\ge1 is fixed, and one fixed alternative among

nMn(r)−r≤Aorr−nmn(r)≤AnM_n^{(r)}-r\le A\qquad\text{or}\qquad r-nm_n^{(r)}\le A

holds for every sufficiently large integer nn, where Mn(r)M_n^{(r)} and mn(r)m_n^{(r)} are the largest and the smallest rr-span (sum of rr consecutive gaps) of the first nn points.

The proposition. There are absolute constants C2,C3>0C_2,C_3>0, depending on nothing, such that the following holds for every sequence of distinct points, every positive integer rr and every A≥1A\ge1 with r≥C2Ar\ge C_2A for which (6.1) holds. With Λ=log⁡(r/A)\Lambda=\log(r/A) (natural logarithm) and S=Ar/Λ2S=\sqrt{Ar}/\Lambda^2, there is a threshold NN, which may depend on rr, AA and the sequence but not on DD, such that for every integer n≥Nn\ge N and every real DD with 0≤D≤S0\le D\le S,

∫T∣Nn((x,x+D/n])−D∣ dx ≤ C3A;\int_{\mathbb T}\Bigl|N_n\bigl((x,x+D/n]\bigr)-D\Bigr|\,dx\ \le\ C_3A ;

that is, for each n≥Nn\ge N the supremum over 0≤D≤S0\le D\le S of the left side is at most C3AC_3A. Conventions: arcs (x,x+D/n](x,x+D/n] are half-open arcs of the circle of length D/nD/n; the conclusion is at integer times, the lemmas at real times; the implied constants are absolute.

Checklist

  • Quantifiers and scope. Correction needed (F1). The page states the eventual quantifier ("for all sufficiently large integers nn") and the clause that the threshold does not depend on DD exactly as the source does, and handles the boundary case D=0D=0. The conclusion is proved at integer times only, as the source proves it, through identity (6.4). The clause "not on DD" is true; the page's justification of it is inaccurate as written.
  • Circularity. Pass. The bound descends from Lemma 6.3 at scale rr through Lemma 6.2 to scale KK and then to D≤SD\le S; nothing equivalent to (6.7) is assumed.
  • Model and convention changes. Pass. The normalization zt=Zt/Dz_t=Z_t/D, the doubling chain and the real-time counting set PtP_t are the source's own objects; no averaged or relaxed system is substituted, and the transfer from real times to integer times is the identity (6.4).
  • Finite and statistical overreach. Inapplicable. No finite case or heuristic average appears.
  • Uniformity. Pass in the mathematics, correction needed in the exposition (F1). The constant C=18C=18 in (6.8) is verified below; the factor (1+Cθ)h(1+C\theta)^h is bounded by an absolute constant because C2C_2 imposes θ<1/2\theta<1/2 and θΛ≤1\theta\Lambda\le1; the threshold in tt behind (6.9) does not involve DD; the threshold of the descent step is uniform over 0<D≤S0<D\le S for the reason given under Weakest steps, which the page does not state.
  • Extremal conclusions. Pass. The only extremal object is the supremum over DD in (6.7); the bound is proved for each DD with a constant free of DD, so the supremum is bounded. No infimum, attainment or sharpness is claimed.
  • Consequences and composition. Pass, with F2 recorded. Each deduction was re-derived: (6.8) from (6.5) with k=⌈D/K⌉k=\lceil D/K\rceil; (6.9) by hh applications of (6.8) and Lemma 6.3; the descent inequality from (6.5) with E=KE=K, k=1k=1 and (6.9) at time (1+θ)t(1+\theta)t; the bound DθΛ≤A/Λ≤AD\theta\Lambda\le A/\Lambda\le A; the passage to integer times. The inputs are consumed at their stated strength except for the uniformity in DD of the Lemma 6.2 threshold, which the Lemma 6.2 Statement does not grant and the page does not derive (F1).
  • Computation. Inapplicable. The page contains no computation.
  • Reproduction. Inapplicable. The page states no rerun commands and makes no computational claim.
  • Source and verdict fidelity. Pass, with F2 recorded. The Statement section agrees clause by clause with Proposition 6.4 on p. 12 of the artifact; the labels (6.1), (6.4), (6.5), (6.7), (6.8), (6.9), Lemma 6.2, Lemma 6.3 and the pages 12--13 are correct; the Standing paragraph claims only an author-recorded reconstruction. The source's reuse of the constant C′C' in the descent display is repaired on the page without being recorded (F2).

Weakest steps

1. The iteration to (6.9). Let D0=K<D1<⋯<Dh=rD_0=K<D_1<\cdots<D_h=r with Di=2iKD_i=2^iK for i<hi<h and Dh=rD_h=r, where hh is the least integer with 2hK≥r2^hK\ge r; then Dh−1<r≤2Dh−1D_{h-1}<r\le2D_{h-1}, so consecutive scales satisfy K≤D≤E≤2DK\le D\le E\le2D, and

h≤log⁡2(r/K)+1=Λ2log⁡2+1,h\le\log_2(r/K)+1=\frac{\Lambda}{2\log2}+1 ,

since r/K=r/Ar/K=\sqrt{r/A}; with Λ>1\Lambda>1 this is at most 1.73 Λ1.73\,\Lambda. (When K=rK=r the chain is empty and (6.9) follows from Lemma 6.3 directly.) Put t0=tt_0=t and ti+1=(1+qi)tit_{i+1}=(1+q_i)t_i, where qi=Di+1/(kir)≤2θq_i=D_{i+1}/(k_ir)\le2\theta and ki=⌈Di/K⌉k_i=\lceil D_i/K\rceil. Applying (6.8) at scale DiD_i and time tit_i for i=0,…,h−1i=0,\ldots,h-1 and substituting each bound into the previous one gives

zt(K) ≤ (1+Cθ)hzth(r)+Cθ∑i<h(1+Cθ)i+∑i<h(1+Cθ)i 4kirtiDi.z_t(K)\ \le\ (1+C\theta)^h z_{t_h}(r) +C\theta\sum_{i<h}(1+C\theta)^i +\sum_{i<h}(1+C\theta)^i\,\frac{4k_ir}{t_iD_i} .

Here zth(r)≤θ2z_{t_h}(r)\le\theta^2 by Lemma 6.3, since th≥tt_h\ge t is late when tt is; (1+Cθ)i≤exp⁡(Cθh)(1+C\theta)^i\le\exp(C\theta h), and with C=18C=18, θ<1/2\theta<1/2 and θΛ≤1\theta\Lambda\le1,

Cθh ≤ 18(θΛ2log⁡2+θ) < 22,C\theta h\ \le\ 18\Bigl(\frac{\theta\Lambda}{2\log2}+\theta\Bigr)\ <\ 22 ,

so the factor is an absolute constant MM. Also ki/Di≤2/Kk_i/D_i\le2/K and ti≥tt_i\ge t, so the last sum is at most 8hr/(Kt)8hr/(Kt). Hence

zt(K) ≤ Mθ2+MC hθ+8MhrKt ≤ CaθΛ+CbhrKt,z_t(K)\ \le\ M\theta^2+MC\,h\theta+\frac{8Mhr}{Kt} \ \le\ C_a\theta\Lambda+\frac{C_bhr}{Kt},

using θ2≤θΛ\theta^2\le\theta\Lambda (as θ<1<Λ\theta<1<\Lambda) and h≤1.73 Λh\le1.73\,\Lambda. For fixed rr, AA and sequence the last term tends to 00, so zt(K)≤(Ca+1)θΛz_t(K)\le(C_a+1)\theta\Lambda for all tt beyond a threshold that depends on rr, AA and the sequence (through the hh Lemma 6.2 thresholds and the Lemma 6.3 threshold) and on nothing else. This is (6.9) with C′=Ca+1C'=C_a+1 absolute. It composes with the descent step by being applied at the time (1+θ)t≥t(1+\theta)t\ge t.

2. The threshold's independence from DD. Fix 0<D≤S0<D\le S. The descent bound Zt(D)≤(8+C′′)A+4r/tZ_t(D)\le(8+C'')A+4r/t at a time tt rests on: (a) (6.9) at the time (1+θ)t(1+\theta)t, whose threshold is free of DD; (b) Lemma 6.2 with the triple (D,K,1)(D,K,1), whose largeness requirement, by the closing sentence of the Lemma 6.2 page's proof, is that (6.1) hold at the integer parts of the times in [t,(1+θ)t][t,(1+\theta)t], that r<⌊t⌋r<\lfloor t\rfloor, and that the arcs of lengths D/tD/t and K/((1+θ)t)K/((1+\theta)t) be shorter than 11; only the first arc involves DD, and D/t≤S/t<1D/t\le S/t<1 once t>St>S. At an integer time nn, identity (6.4) needs D/n≤1D/n\le1 as well: for D>nD>n the arc is the whole circle, Δn≡n−D\Delta_n\equiv n-D has nonzero mean and (6.4) fails. So with NN the largest of the (6.9) threshold divided by 1+θ1+\theta, the (6.1) threshold, r+1r+1, K+1K+1 (which exceeds S+1S+1, since S<KS<K) and 4r/A4r/A, every integer n≥Nn\ge N and every 0<D≤S0<D\le S give ∫∣Δn(⋅,D)∣=2Zn(D)≤2(9+C′′)A\int|\Delta_n(\cdot,D)|=2Z_n(D)\le2(9+C'')A, and D=0D=0 gives 00. The clause "not on DD" of the statement follows. The page reaches the same conclusion with a reason that does not cover (b) (F1).

3. The single-step bound (6.8). For consecutive scales D≤E≤2DD\le E\le2D with D≥KD\ge K and k=⌈D/K⌉k=\lceil D/K\rceil: D/K≥1D/K\ge1 gives D/K≤k≤D/K+1≤2D/KD/K\le k\le D/K+1\le2D/K, so

q=Ekr≤2Dkr≤2Kr=2θ,8kAD≤16AK=16θ,q=\frac E{kr}\le\frac{2D}{kr}\le\frac{2K}r=2\theta,\qquad \frac{8kA}D\le\frac{16A}K=16\theta ,

and q<1q<1 holds because θ<1/2\theta<1/2. Dividing (6.5) by D>0D>0 and writing Z(1+q)t(E)=E z(1+q)t(E)Z_{(1+q)t}(E)=E\,z_{(1+q)t}(E),

zt(D)≤(1+q) z(1+q)t(E)+q+8kAD+4krtD≤(1+18θ) z(1+q)t(E)+18θ+4krtD,z_t(D)\le(1+q)\,z_{(1+q)t}(E)+q+\frac{8kA}D+\frac{4kr}{tD} \le(1+18\theta)\,z_{(1+q)t}(E)+18\theta+\frac{4kr}{tD},

using z≥0z\ge0, 1+q≤1+2θ1+q\le1+2\theta and q+8kA/D≤18θq+8kA/D\le18\theta. This is (6.8) with C=18C=18, as the page states; the source leaves CC unnamed. The letter DD denotes the chain scale here and the short-interval length in the descent, as in the source.

Strongest attack

The attack aimed at the clause that the time threshold does not depend on DD, the one part of the statement beyond the bound itself. The Lemma 6.2 Statement, on its page and in the source, fixes DD before saying "for all sufficiently large tt", so its threshold may depend on DD; the descent step invokes it once for each of the uncountably many D∈(0,S]D\in(0,S], and if the threshold grew without bound as D→0D\to0 or as D→SD\to S, no single nn would serve all DD and (6.7) would fail as a supremum. The attack fails: the threshold's only dependence on DD is the requirement D/t<1D/t<1, monotone in DD and met for all D≤SD\le S by t>St>S; the transport error 8A+4r/t8A+4r/t is free of DD; (6.9) enters at the DD-free time (1+θ)t(1+\theta)t; and the integer-time identity (6.4) needs only D≤nD\le n, again met by n>Sn>S. A second attack tried to make the constant C′C' of (6.9) depend on r/Ar/A through the product (1+Cθ)h(1+C\theta)^h with hh growing like Λ\Lambda; it fails because C2C_2 imposes θΛ≤1\theta\Lambda\le1, giving Cθh<22C\theta h<22. A third attack tried the descent at DD near SS, where the term C′′DθΛC''D\theta\Lambda is largest; it equals C′′A/Λ<0.73 C′′AC''A/\Lambda<0.73\,C''A there, inside the constant. The mathematics survives; the first attack exposes an inaccurate sentence on the page (F1).

Premises

  • Lemma 6.2 (imported from the same folder's reconstruction page; source held, p. 11, statement and proof read from the page image and the text layer, the statement compared clause by clause with the page). Exact interface: under (6.1), for fixed D,E>0D,E>0, integer k≥1k\ge1 and q=E/(kr)<1q=E/(kr)<1, for all sufficiently large tt, Zt(D)≤(1+q)DEZ(1+q)t(E)+qD+8kA+4kr/tZ_t(D)\le\frac{(1+q)D}E Z_{(1+q)t}(E)+qD+8kA+4kr/t; by the page's proof, "sufficiently large" means (6.1) at the integer parts of the times in [t,(1+q)t][t,(1+q)t], kr<⌊t⌋kr<\lfloor t\rfloor, and arcs of lengths D/tD/t and E/((1+q)t)E/((1+q)t) shorter than 11. The page names it as an input; its proof was not verified here.
  • Lemma 6.3 (imported from the same folder's reconstruction page; source held, p. 12, statement and proof read from the image). Exact interface: under (6.1), Zt(r)≤AZ_t(r)\le A for all sufficiently large tt. Not verified here.
  • Identity (6.4) (source p. 11; stated on the Lemma 6.2 page). Exact interface: at an integer time nn and for 0≤D≤n0\le D\le n, ∫T∣Δn(x,D)∣ dx=2Zn(D)\int_{\mathbb T}|\Delta_n(x,D)|\,dx=2Z_n(D). The restriction D≤nD\le n is implicit in the source and supplied here.
  • Hypothesis (6.1) (source p. 10), with A≥1A\ge1 and the section's standing convention that tt is large enough for the spans used to exist.
  • Explicit assumptions. The points are distinct and rr is a positive integer; C2C_2 is large enough that θ<1/2\theta<1/2 (hence Λ=−2log⁡θ>2log⁡2>1\Lambda=-2\log\theta>2\log2>1) and θΛ≤1\theta\Lambda\le1; all implied constants are absolute. No batch acceptance order applies; this is a single focused review.

Findings

F1. Severity: required. Location: "Integer times", the sentence "from the largeness needed by the finitely many comparisons, none of which depends on DD". Defect: the descent step is one Lemma 6.2 instance for each D∈(0,S]D\in(0,S], not finitely many, and its largeness requirement does depend on DD (the arc of length D/tD/t must be shorter than 11), as does identity (6.4) at integer time (D≤nD\le n); both are uniform over 0≤D≤S0\le D\le S once n>Sn>S, but the page does not say so, and the sentence as written is inaccurate at the statement's clause "not on DD". Witness: source p. 13, whose reason is "The transport error above is independent of DD, so one late time works uniformly for 0<D≤S0<D\le S"; Lemma 6.2 page in the same state, Statement ("Fix D,E>0D,E>0 ... for all sufficiently large tt") and the closing sentence of its Proof. Proposed replacement: "The threshold on nn comes from (6.9) at the time (1+θ)n(1+\theta)n, from 4r/n≤A4r/n\le A, from the finitely many chain comparisons behind (6.9), and from the descent comparison, whose transport error 8A+4r/t8A+4r/t is free of DD and whose only DD-dependent largeness requirement (Lemma 6.2 page, end of proof) is that the arc of length D/nD/n be shorter than 11; identity (6.4) needs the same. Since D≤SD\le S, any n>Sn>S meets both at once, so one late time serves every 0≤D≤S0\le D\le S."

F2. Severity: suggested. Location: "Descent to short intervals", "this is at most 8A+C′′DθΛ+4r/t8A+C''D\theta\Lambda+4r/t with C′′C'' absolute". Defect: the source's display writes this line with the constant C′C' of (6.9), which is not literally valid, since (1+θ)C′DθΛ+θD(1+\theta)C'D\theta\Lambda+\theta D exceeds C′DθΛC'D\theta\Lambda; the page's C′′C'' is the correct repair (C′′=2C′+1C''=2C'+1 serves, using θ≤1\theta\le1 and θ≤θΛ\theta\le\theta\Lambda), but the departure from the source is not recorded, and the Standing sentence on constants covers constants the reconstruction names, not a constant the source reuses. Witness: source p. 13, second line of the descent display, "≤8A+C′DθΛ+4r/t\le 8A+C'D\theta\Lambda+4r/t". Proposed replacement: after "with C′′C'' absolute" add "(the source's display writes C′C' here, reusing the constant of (6.9); absorbing θD\theta D and the factor 1+θ1+\theta needs a larger constant, and C′′=2C′+1C''=2C'+1 serves)".

F3. Severity: note. Location: "Proof", "take C2C_2 large enough that θ\theta and θΛ\theta\Lambda are small". The proof also uses 2θ<12\theta<1 (for q<1q<1 in the chain) and Λ≥1\Lambda\ge1 (in "h=O(Λ)h=O(\Lambda)", "θ≤θΛ\theta\le\theta\Lambda" and "A/Λ≤AA/\Lambda\le A"); both follow from θ<1/2\theta<1/2 because Λ=−2log⁡θ\Lambda=-2\log\theta, but the page does not say so. Witness: source p. 13, "taking C2C_2 large enough that θΛ\theta\Lambda is small", equally silent. Proposed replacement: "take C2C_2 large enough that 2θ<12\theta<1 (so q<1q<1 below and Λ=−2log⁡θ>1\Lambda=-2\log\theta>1) and θΛ≤1\theta\Lambda\le1; both hold once r/Ar/A is large."

F4. Severity: note. Location: frontmatter desc, "intervals holding at most S points". The intervals are arcs of length D/nD/n with D≤SD\le S; DD is their mean count over xx, not a bound on their count. Witness: source p. 12, (6.7), whose integrand is Nn((x,x+D/n])−DN_n((x,x+D/n])-D with 0≤D≤S0\le D\le S. Proposed replacement: "intervals of length at most S over n".

Verdict

Source fidelity: faithful with corrections. The Statement section reproduces Proposition 6.4 with its hypotheses, quantifiers, constants, the definition of SS and the clause on the threshold exactly as on p. 12 of the artifact, and every locator and label is correct; the corrections are F1, to the page's own justification of the threshold's independence from DD, and F2, the unrecorded repair of a constant the source reuses.

The argument as reconstructed: sound. Every deduction was re-derived and holds; the closing step's clause "not on DD" is true, but its stated reason does not cover the descent comparison, and F1 supplies the missing observation. No step is defective.

Limitations: Lemma 6.2 and Lemma 6.3 were consumed at their stated interfaces and their proofs were not verified; the review covers pp. 10--13 of the source and says nothing about the rest of the paper or its main theorem; the source is an unrefereed preprint; no computation was involved. This focused review assigns no tier and changes no status.