According to modern cosmology, the universe began with a big bang about 10 billion years ago, and it has been expanding ever since. If the density of mass in the universe is great enough, its gravitational force will cause that expansion to slow down and reverse, causing the universe to fall back in on itself. Then the universe will end in a cataclysmic event known as “the Big Crunch.”
I would like to present to you a vaguely analogous theory of the history of science. The upper curve on Figure 1 was first made by historian Derek da Solla Price, sometime in the 1950s. It is a semilog plot of the cumulative number of scientific journals founded worldwide as a function of time.