  It is proposed that the vacuum admits two different phases as described by
the Chaplygin equation of state or its generalised version: a phase where the
energy density behaves as if dominated by non-relativistic matter and a de
Sitter phase. The particle production due to the expansion that takes place at
the matter-like phase can generate entanglement entropy and provide, through
interactions, the environment that turn gravitational quantum features into
classical ones. In the ensued de Sitter phase, the cosmological constant can be
suppressed by inflation.
