You cannot assume the universe will collapse upon itself again into a singularity. Current understanding of the universe dictates that the universe will expand indefinitely, causing the density of matter and energy to asymptotically approach zero, hence the death of the universe.

Your theory lacks a mechanism to cause the universe to contract after the aforementioned period of expansion. Scientists have already concluded that the force of gravity has been overcome by the mysterious force accelerating the expansion of the universe, which had led to the general acceptance that our universe will die a cold and dark death.