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Banks 2016 limit points sequence normalized prime gaps
corollary_1_2: The set L of limit points of the normalized prime gaps (p_{n+1} - p_n)/log p_n meets [0,T] in Lebesgue measure at least (1 - o(1))T/8 as T tends to infinity, with an ineffective o(1), and in measure greater than T/22 for every T > 0.
theorem_1_1: Banks, Freiberg and Maynard's main theorem: for any nine nonnegative reals beta_1 <= ... <= beta_9, at least one difference beta_j - beta_i with i < j is a limit point of the normalized prime gaps (p_{n+1} - p_n)/log p_n.
theorem_1_3: For each fixed integer m >= 2 and any 8m^2 + 8m nonnegative reals beta_1 <= ... <= beta_{8m^2+8m}, some vector of differences along an increasing chain of m + 1 indices is a limit point of the vectors of m consecutive normalized prime gaps.
Banks, William D. and Freiberg, Tristan and Maynard, James, On limit points of the sequence of normalized prime gaps. Proc. Lond. Math. Soc. (3) 113 (2016), 515-539, doi:10.1112/plms/pdw036. The arXiv record names arXiv's non-exclusive distribution license (arXiv:1404.5094), every other right reserved. The copy read for this card is arXiv:1404.5094v2 (20 October 2014), 25 pages; labels and pages on this card and its result pages are that version's.
Let L be the set of limit points of (p_(n+1) - p_n)/log p_n; the paper states Erdos's conjecture as L = [0, infinity] (p. 1). Before this work 0 and infinity were the only points known to lie in L (p. 1), although Erdos and Ricci had shown that L has positive Lebesgue measure, Hildebrand and Maier that lambda([0,T] cap L) >= cT for all sufficiently large T, and Pintz that L contains [0,c] for an ineffective c > 0 (p. 2). Theorem 1.1 (p. 2) proves that for k = 9 and any nonnegative reals beta_1 <= ... <= beta_9, at least one of the differences beta_j - beta_i (1 <= i < j <= 9) lies in L. Corollary 1.2 (p. 2) deduces lambda([0,T] cap L) >= (1 - o(1))T/8 as T -> infinity, with an ineffective o(1), which the paper reads as at least 12.5% of nonnegative reals lying in L, and the effective bound lambda([0,T] cap L) > T/22 for all T > 0. Theorem 1.3 (p. 3) is the version for chains of gaps: for each fixed integer m >= 2 and any 8m^2 + 8m nonnegative reals beta_1 <= ... <= beta_(8m^2+8m), some vector (beta_J(2) - beta_J(1), ..., beta_J(m+1) - beta_J(m)) with J(1) < ... < J(m+1) is a limit point in [0, infinity]^m of the vectors of m consecutive normalized gaps; the paper calls Theorem 1.1 a stronger version of its case m = 1. The method combines the Erdos-Rankin construction of long runs of composites (Section 5, pp. 17-22) with a uniform version of the Maynard-Tao theorem (Section 4, pp. 6-17), whose Theorem 4.3 (p. 10) rests on a modified Bombieri-Vinogradov theorem, Theorem 4.2 (p. 8); Section 6 (pp. 22-24) deduces Theorems 1.3 and 1.1. Section 7 (p. 24) remarks that if Theorem 4.2 held with an arbitrary fixed theta in (0,1), a minor adaptation of the Maynard-Tao argument would allow k = 5 in Theorem 1.1.
Source: https://arxiv.org/abs/1404.5094.
Read status. Claims checked: Theorem 1.1, Corollary 1.2 and Theorem 1.3 (pp. 2-3) were read clause by clause on the printed pages, and the proof of Corollary 1.2 (pp. 2-3) was read through. The deductions of Section 6 (pp. 22-24) were read for structure only, and Theorem 4.3 (p. 10) and Lemma 5.2 (p. 19) as statements; no other proof was checked, and nothing here is independently reviewed.
Bears on.
- #5: the problem asks, for each C >= 0, for a sequence along which (p_(n+1) - p_n)/log n tends to C; since log p_n/log n -> 1, the C for which such a sequence exists are exactly the finite points of L (an observation of the result pages, not of the paper). Theorem 1.1 puts some difference of any nine nonnegative reals among them, and Corollary 1.2 bounds their measure in [0,T] from below; neither names a particular C, so neither settles an instance of the problem. Theorem 1.3 concerns chains of m >= 2 gaps and is context only.
Results.
- Theorem 1.1 (p. 2): among any nine nonnegative reals some difference lies in L.
- Corollary 1.2 (p. 2): lambda([0,T] cap L) >= (1 - o(1))T/8 as T -> infinity, and lambda([0,T] cap L) > T/22 for all T > 0.
- Theorem 1.3 (p. 3): the version for chains of m >= 2 consecutive gaps, from 8m^2 + 8m nonnegative reals.
No file of this source is held: no license on record permits its redistribution, and the card cites the edition it names above.