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Source. Proposition 2.4, p. 5, of Sébastien Martineau, "On coprime percolation, the visibility graphon, and the local limit of the GCD profile," Electronic Communications in Probability 27 (2022), 1-14, doi:10.1214/21-ECP381; arXiv:1804.06486. Pages are those of the arXiv v2 PDF named on the source card.

Setting

Følner sequences, cop\mathsf{cop}, μF,cop\mu_{F,\mathsf{cop}} and μ∞,cop\mu_{\infty,\mathsf{cop}} are as on Proposition 2.3. For probability measures μ,ν\mu,\nu on Ω{0,1}\Omega_{\{0,1\}}, μ\mu is stochastically dominated by ν\nu if some coupling (W,W′)(\mathcal{W},\mathcal{W}') of (μ,ν)(\mu,\nu) has W⊂W′\mathcal{W}\subset\mathcal{W}' almost surely (p. 5), configurations being read as their sets of white points, as in the proof of Proposition 2.3 (p. 7), where the coupling satisfies ω(x)≤ω∞(x)\omega(x)\le\omega_\infty(x).

Statement

Proposition 2.4 (p. 5). Let d≥1d\ge1 and let (Fn)(F_n) be a Følner sequence of Zd\mathbb{Z}^d. If μFn,cop\mu_{F_n,\mathsf{cop}} converges to some probability measure μ\mu, then μ\mu is stochastically dominated by μ∞,cop\mu_{\infty,\mathsf{cop}}.

Read depth. Claims checked: the statement was read clause by clause on the print. The proof was read but not checked step by step.

Proof pointer

The proof (pp. 6-7) records, for each prime pp, whether a point lies outside pZdp\mathbb{Z}^d; along any Følner sequence this prime-by-prime record converges to its limit law (Lemma 2.6, p. 6, deduced from Lemma 2.8, p. 8). Coprimality is the minimum over primes of these indicators, a map that is only upper semicontinuous, which yields the one-sided comparison rather than convergence (p. 6).

Dependencies

Lemma 2.6 (p. 6); Lemma 2.8 (p. 8).

Bears on

None directly; the result is an ingredient of Proposition 2.3.