  We propose a Dirac type modification of the xp-model to a $x \slashed{p}$
model on a semi-infinite cylinder. This model is inspired by recent work by
Sierra et al on the xp-model on the half-line. Our model realizes the
Berry-Keating conjecture on the Riemann zeros. We indicate the connection of
our model to that of gapped graphene with a supercritical Coulomb charge, which
might provide a physical system for the study of the zeros of the Riemann Zeta
function.
