Evolution of dispersion in the cosmic deuterium abundance
  Deuterium is created during Big Bang Nucleosynthesis, and, in contrast to the
other light stable nuclei, can only be destroyed thereafter by fusion in
stellar interiors. In this paper we study the cosmic evolution of the deuterium
abundance in the interstellar medium and its dispersion using realistic galaxy
evolution models. We find that models that reproduce the observed metal
abundance are compatible with observations of the deuterium abundance in the
local ISM and z ~ 3 absorption line systems. In particular, we reproduce the
low astration factor which we attribute to a low global star formation
efficiency. We calculate the dispersion in deuterium abundance arising from
different structure formation histories in different parts of the Universe. Our
model also predicts an extremely tight correlation between deuterium and metal
abundances which could be used to measure the primordial deuterium abundance.
