Cosmological density perturbation on spin dominated universes and COBE data

Abstract

The evolution equation of cosmic density perturbation of a spin dominated universe in Einstein-Cartan gravity is obtained.Examples of inflationary cosmologies with spin are also given where we compute the density perturbations in terms of redshift and show that spin-torsion effects produce a growth on the inhomogeneity of the universe as the redshift is high.Spin-torsion effects are redshifted out when the Universe expands and would be rarely of importance in present day phase of the universe.Comparison with the primordial density fluctuation of COBE data is also obtained.From our computations a COBE type experiment could be proposed to measure the spin-torsion effects in large scale structure objects such as spiral Galaxies and globular clusters.