Prime gaps: Difference between revisions

From Polymath Wiki
Jump to navigationJump to search
No edit summary
Asdf (talk | contribs)
replace an external link with an interwiki link
 
(One intermediate revision by one other user not shown)
Line 5: Line 5:
A recent result of Goldston-Pintz-Yildirim shows that there exist infinitely many n for which the gap is as small as <math>o(\log p_n)</math> (in fact more precise bounds are known).  But the set of small gaps established by this method is sparse.
A recent result of Goldston-Pintz-Yildirim shows that there exist infinitely many n for which the gap is as small as <math>o(\log p_n)</math> (in fact more precise bounds are known).  But the set of small gaps established by this method is sparse.


[[Cramer's conjecture]] asserts that the prime gap never exceeds <math>O(\log^2 p_n)</math> in size.  If so, this resolves the [[finding primes]] project positively.  However, the best upper bound on the prime gap is <math>O( p_n^{1/2} \log p_n )</math> assuming the Riemann hypothesis, and <math>O( p_n^{0.535} )</math> otherwise (a result of Baker and Harman).
[[Cramer's conjecture]] asserts that the prime gap never exceeds <math>O(\log^2 p_n)</math> in size.  If so, this resolves the [[finding primes]] project positively.  However, the best upper bound on the prime gap is <math>O( p_n^{1/2} \log p_n )</math> assuming the Riemann hypothesis, and <math>O( p_n^{0.525} )</math> otherwise (a result of Baker, Harman, and Pintz; an earlier bound of <math>O(p_n^{0.535})</math> was obtained by Baker and Harman.).


Rankin showed that the prime gap can be as large as <math>\log p_n \frac{\log \log p_n \log \log \log \log p_n}{(\log \log \log p_n)^3}</math>.
Rankin showed that the prime gap can be as large as <math>\log p_n \frac{\log \log p_n \log \log \log \log p_n}{(\log \log \log p_n)^3}</math>.
Line 11: Line 11:
# R. C. Baker and G. Harman, “The difference between consecutive primes,” Proc. Lond. Math. Soc., series 3, 72 (1996) 261–280. MR 96k:11111
# R. C. Baker and G. Harman, “The difference between consecutive primes,” Proc. Lond. Math. Soc., series 3, 72 (1996) 261–280. MR 96k:11111
# K. Soundararajan, [http://arxiv.org/abs/math/0605696 Small gaps between prime numbers: The work of Goldston-Pintz-Yildirim]
# K. Soundararajan, [http://arxiv.org/abs/math/0605696 Small gaps between prime numbers: The work of Goldston-Pintz-Yildirim]
# [http://en.wikipedia.org/wiki/Prime_gap The Wikipedia entry on prime gaps]
# [[wikipedia:Prime_gap|The Wikipedia entry on prime gaps]]

Latest revision as of 15:39, 19 August 2009

If [math]\displaystyle{ p_n }[/math] denotes the n^th prime, then [math]\displaystyle{ p_{n+1}-p_n }[/math] is the n^th prime gap.

On average, the prime number theorem tells us that [math]\displaystyle{ p_{n+1}-p_n }[/math] has size [math]\displaystyle{ O(\log p_n) }[/math].

A recent result of Goldston-Pintz-Yildirim shows that there exist infinitely many n for which the gap is as small as [math]\displaystyle{ o(\log p_n) }[/math] (in fact more precise bounds are known). But the set of small gaps established by this method is sparse.

Cramer's conjecture asserts that the prime gap never exceeds [math]\displaystyle{ O(\log^2 p_n) }[/math] in size. If so, this resolves the finding primes project positively. However, the best upper bound on the prime gap is [math]\displaystyle{ O( p_n^{1/2} \log p_n ) }[/math] assuming the Riemann hypothesis, and [math]\displaystyle{ O( p_n^{0.525} ) }[/math] otherwise (a result of Baker, Harman, and Pintz; an earlier bound of [math]\displaystyle{ O(p_n^{0.535}) }[/math] was obtained by Baker and Harman.).

Rankin showed that the prime gap can be as large as [math]\displaystyle{ \log p_n \frac{\log \log p_n \log \log \log \log p_n}{(\log \log \log p_n)^3} }[/math].

  1. R. C. Baker and G. Harman, “The difference between consecutive primes,” Proc. Lond. Math. Soc., series 3, 72 (1996) 261–280. MR 96k:11111
  2. K. Soundararajan, Small gaps between prime numbers: The work of Goldston-Pintz-Yildirim
  3. The Wikipedia entry on prime gaps