A Kaluza--Klein-like model of the gauge theory of gravity and its cosmological meaning

Abstract: A new Kaluza--Klein-like (KK-like) model of the de Sitter gauge theory of gravity is constructed from the geometry related to the gauge-invariant expressions of the gravitational fields. The model reduces to general relativity with a cosmological constant Lambda when the spin tensor is equal to zero. Moreover, it is shown that among the R-2Lambda+betaS^{abc}S_{abc} models, where beta is a dimensionless parameter and S_{abc} denotes torsion, the KK-like model is the only one that may avert the big-bang singularity of the Robertson--Walker universe filled with a spin fluid.