Abstract:
The standard big bang models of classical cosmology are known to possess three defects. The oldest known defect is the spacetime singularity whose existence seems inevitable within the classical framework. The second defect is the existence of a particle horizon which severly limits communications across the distant parts of the universe whose observed homogeneity therefore becomes inexplicable. Recently a third defect has been highlighted, viz., the required fine tuning of the early universe close to the flat spatial model in order to account for the present range of its mean density.
