Bhadury, SamapanSamapanBhaduryDas, ArpanArpanDasFlorkowski, WojciechWojciechFlorkowskiGowthama, K. K.K. K.GowthamaRyblewski, RadoslawRadoslawRyblewski2025-08-222025-08-222023-07-012331-8422https://doi.org/10.48550/arXiv.2307.12436https://d8.irins.org/handle/IITG2025/18521Semiclassical expansion of the Wigner function for spin-1/2 fermions having an effective spacetime-dependent mass is used to analyze spin-polarization effects. The existing framework is reformulated to obtain a differential equation directly connecting the particle spin tensor with the effective mass. It reflects the conservation of the total angular momentum in a system. In general, we find that the gradients of mass act as a source of the spin polarization, although this effect is absent for simple boost-invariant dynamics.en-USWigner functionSpin polarizationSemiclassical expansionSpacetime-dependent massVanishing spin tensore-Printe-Print123456789/615