  The large complex zeros of the Jost function (poles of the S matrix) in the
complex wave number-plane for s-wave scattering by truncated potentials are
associated to the distribution of large prime numbers as well as to the
asymptotic behavior of the imaginary parts of the zeros of the Riemann zeta
function on the critical line. A variant of the Hilbert and Polya conjecture is
proposed and considerations about the Dirac sea as ``virtual resonances'' are
briefly discussed.
