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Maynard 2015 small gaps between primes
proposition_4_2: Maynard's sieve criterion: if the primes have level of distribution theta, then for every admissible k-set at least the ceiling of theta M_k / 2 of the translates n + h_i are prime for infinitely many n, where M_k is a supremum of ratios of integrals of functions on the simplex.
theorem_1_1: Maynard's theorem that for every natural number m the gap p_{n+m} - p_n spanning m consecutive prime gaps is at most a constant times m^3 e^{4m} for infinitely many n, so bounded intervals contain any fixed number of primes infinitely often.
theorem_1_2: Maynard's theorem that for r large in terms of m, among the m-element subsets of any set of r distinct integers, a proportion bounded below in terms of m are sets whose translates are all prime for infinitely many n.
theorem_1_3: Maynard's unconditional theorem that consecutive primes differ by at most 600 infinitely often, proved from the Bombieri-Vinogradov theorem alone.
theorem_1_4: Maynard's conditional theorem that if the primes have level of distribution theta for every theta < 1, then consecutive primes differ by at most 12, and primes two apart by at most 600, infinitely often.
Maynard, James, Small gaps between primes. Ann. of Math. (2) 181 (2015), no. 1, 383-413, doi:10.4007/annals.2015.181.1.7. The arXiv record names arXiv's non-exclusive distribution license (arXiv:1311.4600), every other right reserved. The copy read for this card is arXiv:1311.4600v3.
Theorem 1.1 proves that liminf_n (p_{n+m} - p_n) << m^3 e^{4m} for every m in N, so bounded gaps hold for every fixed number of primes, not just pairs; the abstract records the explicit consequences liminf(p_{n+1} - p_n) <= 600 unconditionally and, under the Elliott-Halberstam conjecture, liminf(p_{n+1} - p_n) <= 12 and liminf(p_{n+2} - p_n) <= 600 (Theorems 1.3 and 1.4). Theorem 1.2 shows that, for r large in terms of m, among the m-element subsets of any set of r distinct integers a proportion >>m 1 consists of sets {h_1, ..., h_m} with n + h_1, ..., n + h_m all prime for infinitely many n, which the paper reads as a positive proportion of admissible m-tuples satisfying the prime m-tuples conjecture "in an appropriate sense" (p. 2). The method is a refinement of the Goldston-Pintz-Yildirim sieve using a multidimensional class of weights, which removes the theta = 1/2 barrier in the level of distribution and so needs only Bombieri-Vinogradov rather than Zhang's stronger equidistribution result. The paper notes that Tao independently obtained Theorem 1.1 with a slightly weaker bound by a similar method, and that the results extend to primes in short intervals, in arithmetic progressions, and to simultaneous prime values of linear forms. This bears on problem 6 (infinitely many n with d_n < d{n+1} < d_{n+2}) only as input: Banks, Freiberg and Turnage-Butterbaugh apply the Maynard-Tao theorem for admissible tuples of linear forms, which this paper states as a remark in its introduction (p. 2); for shifts n + h_i it is Proposition 4.2 with the large-k step (4.5) of Section 4 (every admissible k-set with k >= C m^2 e^{4m} has at least m + 1 primes among the n + h_i for infinitely many n). The constant 600 is Theorem 1.3 (k = 105), not Theorem 1.1 with m = 1, which gives only liminf(p_{n+1} - p_n) << e^4 with an unspecified constant.
Source: https://arxiv.org/abs/1311.4600.
Bears on. #6: the paper does not decide the question, which asks for infinitely many n with d_n < d_{n+1} < d_{n+2}; its results give several primes among the translates of an admissible set, not consecutive primes with ordered gaps. Banks, Freiberg and Turnage-Butterbaugh answer it yes using the Maynard-Tao theorem for admissible tuples of linear forms, in Granville's formulation, as input. Its shift case is Proposition 4.2 with the large-k step (4.5). For linear forms the paper has only the unnumbered remark on p. 2, stated for positive integer coefficients and without a separate proof.
Results. Pages are the printed pages of arXiv:1311.4600v3.
- Theorem 1.1 (p. 2): for every m in N, liminf_n (p_{n+m} - p_n) << m^3 e^{4m}.
- Theorem 1.2 (p. 2): for r sufficiently large depending on m and any set A of r distinct integers, the m-subsets {h_1, ..., h_m} of A with n + h_1, ..., n + h_m all prime for infinitely many n make up a proportion >>_m 1 of all m-subsets of A.
- Theorem 1.3 (p. 3): liminf (p_{n+1} - p_n) <= 600.
- Theorem 1.4 (p. 3): if the primes have level of distribution theta for every theta < 1, then liminf (p_{n+1} - p_n) <= 12 and liminf (p_{n+2} - p_n) <= 600.
- Proposition 4.2 (p. 5): if the primes have level of distribution theta > 0, then for every admissible {h_1, ..., h_k} at least ceil(theta M_k / 2) of the n + h_i are prime for infinitely many n; Proposition 4.3 (p. 6) gives M_5 > 2, M_105 > 4 and M_k > log k - 2 log log k - 2 for large k.
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