Chaplygin gas and effective description of inhomogeneous universe models in general relativity

Understand

In the framework of spatially averaged inhomogeneous cosmologies in classical general relativity, effective Einstein equations govern the dynamics of averaged scalar variables in a scale--dependent way.

• A particular cosmology may be characterized by a cosmic equation of state, closing the hierarchy of effective equations.
• In this context a natural candidate is provided by the Chaplygin gas, standing for a unified description of dark energy and dark matter.
• In this paper, we suppose that the inhomogeneous properties of matter and geometry obey the Chaplygin equation of state.