Linear Equations in Primes
Abstract
Description
Consider a system Ψof non-constant affine-linear forms ψ_1,...,ψ_t: Z^d -> Z, no two of which are linearly dependent. Let N be a large integer, and let K be a convex subset of [-N,N]^d. A famous and difficult open conjecture of Hardy and Littlewood predicts an asymptotic, as N -> \infty, for the number of integer points n in K for which the integers ψ_1(n),...,ψ_t(n) are simultaneously prime. This implies many other well-known conjectures, such as the Hardy-Littlewood prime tuples conjecture, the twin prime conjecture, and the (weak) Goldbach conjecture. <p>
In this paper we (conditionally) verify this asymptotic under the assumption that no two of the affine-linear forms ψ_1,...,ψ_t are affinely related; this excludes the important ``binary'' cases such as the twin prime or Goldbach conjectures, but does allow one to count ``non-degenerate'' configurations such as arithmetic progressions. Our result assumes two families of conjectures, which we term the Inverse Gowers-norm conjecture GI(s) and the Mobius and Nilsequences Conjecture MN(s), where s \in {1,2,...} is the complexity of the system and measures the extent to which the forms ψ_i depend on each other. For s = 1 these are essentially classical, and the authors recently resolved the cases s = 2.<p>
Our results are therefore unconditional in the case s = 2, and in particular we can obtain the expected asymptotics for the number of 4-term progressions p_1 < p_2 < p_3 < p_4 <= N of primes, and more generally for any (non-degenerate) problem involving two linear equations in four prime unknowns.
84 pages, numerous small changes made in the light of comments from the referees
84 pages, numerous small changes made in the light of comments from the referees