  The hot Big-Bang standard model for the evolution of the universe, despite
strong successes, lets unresolved a number of problems. One of its main
drawbacks, known as the horizon problem, was until now thought to be only
solvable by an inflationary scenario. Here is proposed a class of inhomogeneous
models of universe, getting rid of some of the worst drawbacks of standard
cosmology. The horizon problem is solved by means of an initial singularity of
"delayed" type and without need for any inflationary phase. The flatness and
cosmological constant problems disappear.
