At the Edge of Time: Exploring the Mysteries of Our Universe’s First Seconds (Science Essentials Book 32)

by Dan Hooper

In the history of cosmology, no observations or measurements have borne as much fruit as those of the cosmic microwave background. Providing us with a detailed snapshot of our universe 380,000 years after the Big Bang, this collection of photons represents by far the greatest body of information we have about our universe’s youth. Among other things, if we had never observed the cosmic microwave background, we would know virtually nothing about inflation—in fact we would have had little reason to think that something like inflation took place at all. It was by scrutinizing the cosmic microwave background that we learned that our universe is so geometrically flat and uniform—precisely the features that inflation was originally proposed to explain. Furthermore, modern observations of this radiation have shown that the patterns of its temperature variations closely match what is predicted by most theories of inflation. These observations have convinced most cosmologists that something like inflation likely took place. That said, we still know very little about how this occurred, or how it came to an end.