Large gaps between primes (Q291018)

After his impressive work on small gaps between primes, this author tackles large gaps between primes achieving significant progress on this problem. The problem investigated is to show that \(g(x)=\sup_{p_n\leq x} (p_{n+1}-p_n)\) is large, where \(p_n\) is the \(n\)th prime. \textit{P. Erdős} [Duke Math. J. 6, 438--441 (1940; Zbl 0023.29801)], then \textit{R. A. Rankin} [J. Lond. Math. Soc. 13, 242--247 (1938; Zbl 0019.39403)] showed in the forties that NEWLINE\[NEWLINE g(x)\geq (c+o(1)) \log x \log\log x \log\log\log\log x (\log\log\log x)^{-2}, NEWLINE\]NEWLINE with \(c=1/3\). All subsequent improvements have been in improving on the value of \(c\). Before this paper, the best value of \(c\) was \(2 e^{\gamma}\), a result of \textit{J. Pintz} [J. Number Theory 63, No. 2, 286--301 (1997; Zbl 0870.11056)]. In the paper under review, the author shows that \(c\) can be taken to be arbitrarily large by proving that NEWLINE\[NEWLINE \limsup_{n\to\infty} \frac{p_{n+1}-p_n}{(\log p_n) (\log\log p_n) (\log\log\log\log p_n) (\log\log\log p_n)^{-2}}=\infty. NEWLINE\]NEWLINE He follows closely the Erdős-Rankin construction as explained in the paper by \textit{H. Maier} and \textit{C. Pomerance} [Trans. Am. Math. Soc. 322, No. 1, 201--237 (1990; Zbl 0706.11052)] by incorporating sieve ideas from the author's work on small gaps between primes [Ann. Math. (2) 181, No. 1, 383--413 (2015; Zbl 1306.11073)] as well as from the \textit{D. H. J. Polymath} project [Res. Math. Sci. 1, Paper No. 12, 83 p. (2014; Zbl 1365.11110); erratum ibid. 2, Paper No. 15, 2 p. (2015)]. The author notes that the same result has been obtained independently by Ford, Green, Konyagin and Tao by incorporating results on linear equations in primes into the same Erdős-Rankin construction.