Revival of the unified dark energy–dark matter model?

TLDR: In this article, the generalized Chaplygin gas (GCG) proposal for unification of dark energy and dark matter is considered and it admits an unique decomposition into dark energy components once phantomlike dark energy is excluded.

Abstract: We consider the generalized Chaplygin gas (GCG) proposal for unification of dark energy and dark matter and show that it admits an unique decomposition into dark energy and dark matter components once phantomlike dark energy is excluded. Within this framework, we study structure formation and show that difficulties associated to unphysical oscillations or blowup in the matter power spectrum can be circumvented. Furthermore, we show that the dominance of dark energy is related to the time when energy density fluctuations start deviating from the linear $\ensuremath{\delta}\ensuremath{\sim}a$ behavior.