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arXiv · 2604.03343

Friedmann cosmology with fluids and hyperfluids

Ilaria Andrei·Damianos Iosifidis·Laur Järv·Margus Saal
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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.

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Ilaria Andrei, Damianos Iosifidis, Laur Järv, Margus Saal. 2026-04-03. Friedmann cosmology with fluids and hyperfluids. https://doi.org/10.1088/1742-6596%2F3177%2F1%2F012033

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