Friedmann cosmology with fluids and hyperfluids

Abstract

We discuss flat Friedmann-Lemaitre-Robertson-Walker (FLRW) metric-affine cosmology where the metric and connection as well as the matter energy-momentum and hypermomentum all obey the symmetry of spatial homogeneity and isotropy. In particular, we outline a scenario where a dark dust fluid carries spin hypermomentum which makes its effective equation of state dynamical and might relate to the DESI DR2 data.

Figures (1)

• Figure 1: Cosmological evolution of the model with hypermomentum spin ($b=1/3$, $\mathrm{w}_\upsilon=0$).