Montgomery's Pair Correlation Conjecture

In mathematics, Montgomery's pair correlation conjecture is a conjecture made by Hugh Montgomery (1973) that the pair correlation between pairs of zeros of the Riemann zeta function (normalized to have unit average spacing) is

which, as Freeman Dyson pointed out to him, is the same as the pair correlation function of random Hermitian matrices. Informally, this means that the chance of finding a zero in a very short interval of length 2πL/log(T) at a distance 2πu/log(T) from a zero 1/2+iT is about L times the expression above. (The factor 2π/log(T) is a normalization factor that can be thought of informally as the average spacing between zeros with imaginary part about T.) Andrew Odlyzko (1987) showed that the conjecture was supported by large-scale computer calculations of the zeros. The conjecture has been extended to correlations of more than 2 zeros, and also to zeta functions of automorphic representations (Rudnick & Sarnak 1996). In 1982 a student of Montgomery's, A. E. Ozluk, proved the pair correlation conjecture for some of Dirichlet's L-functions.

It is not impossible that the connection with random unitary matrices could lead to a proof of Riemann hypothesis. Both David Hilbert and G. Pólya conjectured that the zeros of the Riemann Zeta function correspond to the eigenvalues of a linear operator, and a proof of their conjecture would imply RH, and some people think this is a promising approach.Andrew Odlyzko (1987)

Montgomery was studying the Fourier transform F(x) of the pair correlation function, and showed (assuming the Riemann hypothesis) that it was equal to |x| for |x|<1. His methods were unable to determine it for |x|≥1, but he conjectured that it was equal to 1 for these x, which implies that the pair correlation function is as above.