Generalized dark matter model with the Euclid satellite

Understand

The concordance model in cosmology, $\Lambda$CDM, is able to fit the main cosmological observations with a high level of accuracy.

• However, around 95% of the energy content of the Universe within this framework remains still unknown.
• In this work we focus on the dark matter component and we investigate the generalized dark matter (GDM) model, which allows for non-pressure-less dark matter and a non-vanishing sound speed and viscosity.
• We first focus on current observations, showing that GDM could alleviate the tension between cosmic microwave background and weak lensing observations.