Spinor field in Bianchi type-I cosmology with Lyra’s geometry

In this study, we examine the role of a nonlinear spinor field in the evolution of the Universe within the framework of a Bianchi type-I cosmological model with Lyra’s geometry. Previous research has explored the nonlinear spinor field in various anisotropic and isotropic cosmological models, revealing that the presence of nontrivial, non-diagonal components of the spinor field’s energy-momentum tensor imposes severe restrictions on both the space-time geometry and the spinor field itself. In our current study, we find that while these restrictions still apply, the introduction of Lyra’s geometry significantly influences the evolution of the Universe. This influence arises from the fact that the invariants of the spinor field are dependent on the parameter of Lyra’s geometry.