Effective dark energy through spin-gravity coupling

We investigate cosmological scenarios with spin-gravity coupling. In particular, due to the spin of baryonic and dark matter particles its coupling gravity, they probe an effective spin-dependent metric, which can be calculated semi-classically in Mathisson-Papapetrou-Tulczyjew-Dixon formalism. Hence, usual field equations give rise modified Friedmann equations, extra terms identified as dark-energy sector. Additionally, we obtain interaction between sectors. case where switches off, recover standard $\Lambda$CDM cosmology. perform a dynamical system analysis find matter-dominated point that describe era, stable late-time solution corresponding acceleration domination. For small values parameter, deviations from concordance scenario are small, however for larger brought desired amount, leading different equation-of-state parameter behavior, well transition redshift deceleration. Finally, confront model predictions Hubble function data.