On the stability of cosmological metrics in Einstein-Cartan cosmologies
  Two metric perturbations in Einstein-Cartan cosmology are examined.The first case is the scalar mode perturbation of de Sitter metric in Einstein-Cartan cosmology.In this case small perturbations of de Sitter metric shows that this metric is unstable for a universe with spin-torsion density and dilaton fields.In the second case we show that the Friedmann metric in the same space is also unstable under the small perturbations. 
L.C.Garcia de Andrade