Alphabeta Math
LemmaStatement: AI-generatedProof: AI-generated
How statement and proof provenance work

The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.

  • Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
  • AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
  • AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.

These labels describe origin, not correctness: citations and verification chips remain separate evidence.

Normalize the logarithmic random graph for nonbacktracking estimates

Statement

Fix γ>1, put L=log⁡n, μ=γL, p=μ/n, and let A be the adjacency matrix of G(n,p). For all sufficiently large integers n, 0<p<1 and H=(A−EA)/μ is real symmetric with independent mean-zero upper-triangular entries, zero diagonal, and max⁡i∑jE∣Hij∣2≤1,max⁡i,jE∣Hij∣2≤1/n,max⁡i,j∣Hij∣≤1/μ. Also EA=p(J−I), A−pJ=μH−pI, and 1≤q=μ≤n1/10 eventually.

Facts & Assumptions

[F1]

For G(n,p), Aij=Aji for i≠j is the indicator of the unordered edge {i,j}, and Aii=0. The indicators for distinct unordered edges are independent Bernoulli(p) variables, taking values 1 and 0 with probabilities p and 1−p, respectively (The Erdős-Rényi finite random graph G(n,p), The adjacency matrix of a finite simple graph, Bernoulli random variables and binomial random variables as sums of independent Bernoulli trials).

[F2]

Expectation on a finite probability space is the weighted sum over its outcomes (Expectation of a real random variable on a finite probability space).

[F3]

The article centers the adjacency matrix at pJ (Centered graph matrices and reference degree).

[F4]

For every a>0, log⁡n/na→0 (The logarithm grows more slowly than every positive real power).

[F5]

The integral logarithm is strictly increasing on (0,∞) and unbounded above, and equals the natural logarithm there (The integral logarithm is continuous and strictly increasing on (0,∞), The integral logarithm is unbounded above and below, The integral logarithm L is the published natural logarithm).

Proof

Given: The objects and hypotheses in the Statement.

Goal: Prove its conclusions.

1.1F1F2F3givenalgebra

For i≠j, EAij=p and E(Aij−p)2=p(1−p) by the two Bernoulli outcomes. Hence Hij has mean zero, variance p(1−p)/μ≤1/n and absolute value at most 1/μ. Its row variance sum is (n−1)p(1−p)/μ≤1. The diagonal vanishes, and symmetry and independence follow from the edge coordinates. The mean matrix and centering identities follow entry by entry.

2.1F4F5step 1.1algebra∎

For any real M, [F5] gives b>0 with log⁡b>M; monotonicity then gives log⁡n≥log⁡b>M for every integer n≥b. Thus log⁡n→∞ and μ=γlog⁡n→∞. By [F4] with a=1 and a=1/5, p=γlog⁡n/n→0 and μ/n1/5→0. Consequently, for all sufficiently large integers n, μ≥1, 0<p<1, and μ≤n1/5, giving 1≤q=μ≤n1/10.

Depends on

Used by · 2

Dependency tree · 2 levels

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