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Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

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Source. Theorem 13, p. 22, of Robert V. Moody, Model Sets: A Survey, in From Quasicrystals to More Complex Systems (Les Houches School lecture notes), Springer/EDP Sciences (2000), 145-166, doi:10.1007/978-3-662-04253-3_6, read in the preprint arXiv:math/0002020v1 (2 Feb 2000) named on the source card; pages here are that preprint's pages, and the book pagination was not compared.

Read depth. Claims checked: the statement and its setting were read clause by clause on the printed pages. The survey gives no proof. Nothing here is independently reviewed.

Statement

Setting (pp. 20-22). Λ=Λ(W)\Lambda=\Lambda(W) is a regular model set (Section 7 fixes this on p. 20), T^\hat{\mathbb T} is the dual group of T=(Rd×G)/L~\mathbb T=(\mathbb R^d\times G)/\tilde L, π^2\hat\pi_2 is the projection to G^\hat G in the dual picture (display (5), p. 6), and w(k)w(k) is the weight of the Bragg peak at π^1(k)\hat\pi_1(k) in Theorem 12.

Theorem 13 (p. 22, quoted). "Let k∈T^k\in\hat{\mathbb T} and let χ\chi denote the characteristic (or indicator) function of WW. Then w(k)=∣χ^(−π^2(k))/vol(W)∣2w(k)=|\hat\chi(-\hat\pi_2(k))/\mathrm{vol}(W)|^2."

The survey calls this the quantitative counterpart of Theorem 12 and attributes it to Meyer (reference [26]).

Proof pointer

No proof is given in the survey.

Dependencies

Theorem 12 and the definitions of Section 2.

Bears on

  • Problem 188: the paper does not mention the problem. It is a survey of the cut-and-project construction of aperiodic point sets; it says nothing about unit distances, two-colorings of the plane or arithmetic progressions, and gives no coloring and no bound on the number of terms the problem asks about.