Cosmic no-hair conjecture in Einstein-Cartan theory

Abstract

We prove the cosmic no-hair conjecture in the Einstein-Cartan theory by taking into account the effects due to the spin of matter. If the ordinary matter forming the cosmological fluid satisfies the dominant and strong energy conditions and the anisotropy energy σ2 is larger than the spin energy S2 (i.e. σ2 - S2 ≥ 0), then all initially expanding Bianchi cosmologies-except type IX-evolve toward the de Sitter spacetime on a Hubble expansion time √3/Λ. The behavior of the Bianchi type IX Universe is similar, provided that the cosmological constant is larger than the half of the largest scalar spatial curvature (3) Rmax.