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Grepstad lev 2014 bounded discrepancy rotation

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corollary_3: Grepstad and Lev's characterization of the Riemann measurable bounded remainder sets for the rotation by an irrational vector alpha: exactly the sets equidecomposable, by translations in Z alpha + Z^d, to a parallelepiped spanned by vectors of Z alpha + Z^d.

proposition_2_4: Grepstad and Lev's form of Kesten's theorem: the measure of every bounded remainder set for the rotation by an irrational vector alpha is an integer combination of 1, alpha_1, ..., alpha_d; for an interval in dimension one this is Kesten's necessity.

theorem_1: Grepstad and Lev's first main result: for an irrational vector alpha in R^d, every parallelepiped spanned by vectors of Z alpha + Z^d has bounded remainder, the d-dimensional extension of the Hecke-Ostrowski theorem.

theorem_2: Grepstad and Lev's second main result: any two Riemann measurable bounded remainder sets of the same measure can be cut into finitely many Riemann measurable pieces and reassembled into each other by translations by vectors of Z alpha + Z^d only.

theorem_2_6: Grepstad and Lev's statement and short proof of the Hecke-Ostrowski theorem: for irrational alpha, every interval of the real line whose length lies in Z alpha + Z is a bounded remainder set, independently of its position.

theorem_3: Grepstad and Lev's characterization of the convex polygons in R^2 that are bounded remainder sets for the rotation by an irrational vector alpha: central symmetry plus two conditions in Z alpha + Z^2 on each pair of parallel edges.

theorem_4: Grepstad and Lev's necessary condition for a convex polytope in R^d to be a bounded remainder set for the rotation by an irrational vector alpha: it is centrally symmetric and its (d-1)-dimensional faces are centrally symmetric.

theorem_5: Grepstad and Lev's description of the invertible linear maps T of R^d that send every Riemann measurable bounded remainder set for an irrational vector alpha to a bounded remainder set for beta: exactly those with T(Z alpha + Z^d) contained in Z beta + Z^d.

theorem_6: Grepstad and Lev's result that every Riemann measurable bounded remainder set for the rotation by an irrational vector alpha has a Riemann integrable solution g of the cohomological equation.


Sigrid Grepstad and Nir Lev, Sets of bounded discrepancy for multi-dimensional irrational rotation, arXiv:1404.0165v2 (2014; published Geom. Funct. Anal. 25 (2015), no. 1, 87-133, DOI 10.1007/s00039-015-0313-z, checked against Crossref on 2026-10-07; 39 pp.).

The multi-dimensional theory of bounded remainder sets. Here α=(α1,…,αd)\alpha=(\alpha_1,\dots,\alpha_d) has 1,α1,…,αd1,\alpha_1,\dots,\alpha_d linearly independent over the rationals, and a measurable set SS is a bounded remainder set when the discrepancy Dn(S,x)=∑k=0n−1χS(x+kα)−n mes SD_n(S,x)=\sum_{k=0}^{n-1}\chi_S(x+k\alpha)-n\,\mathrm{mes}\,S is at most a constant C(S,α)C(S,\alpha) in absolute value for every nn and almost every xx (pp. 1--2, 6); in dimension one the condition says that α\alpha is irrational. Theorem 1 (p. 2) shows that a parallelepiped in Rd\mathbb R^d whose spanning vectors all lie in Zα+Zd\mathbb Z\alpha+\mathbb Z^d has bounded remainder (extending Hecke-Ostrowski), and Corollary 3 (p. 3), drawn from Theorems 1 and 2 and Corollary 2, characterizes the Riemann measurable bounded remainder sets as those equidecomposable to such a parallelepiped using translations by vectors in Zα+Zd\mathbb Z\alpha+\mathbb Z^d only. Relevance: Characterizes the Riemann measurable bounded remainder sets for multi-dimensional irrational rotation, the direct generalization of the one-dimensional Hecke-Ostrowski-Kesten characterization, which the paper recalls (p. 2): an interval is a bounded remainder set exactly when its length lies in Zα+Z\mathbb Z\alpha+\mathbb Z. The paper's section 2 states the two halves of that criterion with short proofs: Proposition 2.4 (p. 8), that the measure of every bounded remainder set lies in Z+Zα1+⋯+Zαd\mathbb Z+\mathbb Z\alpha_1+\cdots+\mathbb Z\alpha_d, and Theorem 2.6 (p. 9, Hecke-Ostrowski), that every interval with length in Zα+Z\mathbb Z\alpha+\mathbb Z is a bounded remainder set. Problem 998's corrected statement asks for the necessity half for an interval [u,v)[u,v) with 0≤u<v≤10\le u<v\le1 and v−u<1v-u<1, counted along the orbit from one point. The criterion constrains only the length, so every translate of a bounded remainder interval is again one, and bounded remainder does not force the endpoints to be fractional parts of multiples of α\alpha, as the site's wording of the problem asks.

The copy read for this card is arXiv:1404.0165v2 (22 October 2014, 39 pp.). Read status: claims checked for every result linked below, read clause by clause on the page images with the definitions of pp. 1--3 and 6--7; the depth of each proof's reading is recorded on its result page, and no proof was checked step by step. The arXiv record names arXiv's non-exclusive distribution license (arXiv:1404.0165), every other right reserved.

Bears on. #998: in dimension one, Proposition 2.4 together with Proposition 2.2 yields the problem's corrected statement (a bounded-discrepancy interval [u,v)[u,v) with 0≤u<v≤10\le u<v\le1 and v−u<1v-u<1 has v−u={jα}v-u=\{j\alpha\}), a derivation written out on the Proposition 2.4 page and not printed in the paper; Theorem 2.6 is the converse, which the problem page credits to Hecke and Ostrowski. The problem page credits the corrected statement to Kesten. The paper recalls the one-dimensional criterion and does not treat the problem itself, and neither result says anything about the endpoints that the site's wording asks about.

Results. Theorem 1 (p. 2, with Corollaries 1 and 2 and Theorem 3.8); Theorem 2 (p. 3); Corollary 3 (p. 3); Theorem 3 (p. 4); Theorem 4 (p. 5, with Corollary 4); Theorem 5 (p. 5, with Corollary 5); Theorem 6 (p. 6); Proposition 2.4 (p. 8); Theorem 2.6 (p. 9).

No file of this source is held: no license on record permits its redistribution, and the card cites the edition it names above.