We consider a model where both dark energy and dark matter originate from the
coupling of a scalar field with a non-conventional kinetic term to, both, a
metric measure and a non-metric measure. An interacting dark energy/dark matter
scenario can be obtained by introducing an additional scalar that can produce
non constant vacuum energy and associated variations in dark matter. The
phenomenology is most interesting when the kinetic term of the additional
scalar field is ghost-type, since in this case the dark energy vanishes in the
early universe and then grows with time. This constitutes an "inverse
quintessence scenario", where the universe starts from a zero vacuum energy
density state, instead of approaching it in the future.Comment: 13 pages; minor changes with references adde
