random matrix theory, number theory,
L-functionsRecent results of Katz and Sarnak [9,10] suggest that the lowlying zeros of families of L-functions display the statistics of the eigenvalues of one of the compact groups of matrices U (N ), O(N) or U Sp (2 N ). We here explore the link between the value distributions of the L-functions within these families at the central point s = 1/2 and those of the characteristic polynomials Z (U, 3 ) of matrices U with respect to averages over SO (2N) and U Sp ( 2N) at the corresponding point 3 = 0, using techniques previously developed for U (N) in [7]. For any matrix size N we find exact expressions for the moments of Z (U, 0 ) for each ensemble, and hence calculate the asymptotic (large N ) value distributions for Z (U, 0) and log Z (U, 0). The asymptotic results for the integer moments agree precisely with the few corresponding values known for L-functions. The value distributions suggest consequences for the non-vanishing of Lfunctions at the central point.