The recent flurry of reports suggesting difficulties with our understanding of the evolution of the universe has led the author to consider a new universal scale factor that specifies the expansion of the universe. Remarkably, it well describes the universe’s growth in the large starting from the Big Bang up to the present. But, surprisingly, the growth is punctuated by a major, hitherto unremarked, dip in growth that the author calls the Big Dip. It occurs about the time of the transition from a radiation-dominated to a matter-dominated universe.

The implications of the universal scale factor are presented in a large number of plots of the Hubble Constant, the scale factor, energy density, pressure, and so on that provide a complete picture of the large scale growth of the universe.

After describing the universal scale factor theory the author justifies its form by a close analogy with electron vacuum polarization in QED. This requires we view the entire history of the universe simultaneously. The universe grows in the vacuum.

Based on this analogy the book suggests a new unknown interaction (force) that guides the growth of the energy density of the universe, and thereby determines its expansion (and contraction).