Axino dark matter from Q-balls in Affleck-Dine baryogenesis and the   $\Omega_b - \Omega_{DM}$ coincidence problem
  We show that the $\Omega_b - \Omega_{DM}$ coincidence can naturally be explained in a framework where axino cold dark matter is predominantly produced in non-thermal processes involving decays of Q-balls formed in Affleck-Dinebaryogenesis. In this approach the similarity between $\Omega_b$ and $\Omega_{DM}$ is a direct consequence of the (sub-)GeV scale of the mass of the axino. 
Leszek Roszkowski and Osamu Seto