Since the birth of the Universe

Subsequent modelling of the universe explored the possibility that the cosmological constant, may result in an expanding universe, transformed cosmology from a highly speculative science into a predictive science, Cosmic inflation, ( modification of standard Big Bang model). In cosmological structures to predict the Universes past and future require an accurate theory of gravitation. When the word first got out that the expansion of the universe was accelerating, many astronomers questioned. The whole concept was so difficult to believe because it requires significant changes in our understanding of the way the universe works. Before the discovery of dark energy, scientists had two models of how the universes expansion would work. There are three scenarios- Big Crunch, big Chill, Big Rip. So out of the three scenarios for the fate of the universe - re-collapse to a Big Crunch, expand ever more slowly to a Big Chill, or expand ever faster to a Big Rip - we have managed to narrow the possibilities down somewhat. No matter which scenario is right, the universe still has at least a few tens of billions of years left - which leaves us plenty of time to look for the answers.