Is it possible to consider Dark Energy and Dark Matter as a same and unique Dark Fluid?

TL;DR

This paper explores the possibility that dark matter and dark energy are unified into a single dark fluid, analyzing observational data and theoretical models to constrain such a hypothesis.

Contribution

It reviews observational constraints and theoretical models for a unified dark fluid, proposing an alternative to the standard two-component dark universe model.

Findings

Constraints on dark fluid properties from supernovae and CMB data

Potential models for unifying dark matter and dark energy

Implications for cosmological evolution and structure formation

Abstract

In the standard model of cosmology, the present evolution of the Universe is determined by the presence of two components of unknown nature. One of them is referenced as ``dark matter'' to justify the fact that it behaves cosmologically like usual baryonic matter, whereas the other one is called ``dark energy'', which is a component with a negative pressure. As the nature of both dark components remains unknown, it is interesting to consider other models. In particular, it seems that the cosmological observations can also be understood for a Universe which does not contain two fluids of unknown nature, but only one fluid with other properties. To arrive to this conclusion, we will review the observational constraints from supernovae of type Ia, cosmic microwave background, large scale structures, and the theoretical results of big-bang nucleosynthesis. We will try to determine constraints on this unifying ``dark fluid'', and briefly review different possibilities to build models of dark fluid.