The Cosmic Microwave Background was created as the first atoms formed hundreds of thousands of years after the Big Bang, and it retains information about the formation of the Universe. Discovering it existed confirmed a key prediction of the Big Bang Model and won its discoverers a Nobel Prize. Another Nobel went to the team behind the Cosmic Background Explorer, which gave us our first look at some of the details of the Cosmic Microwave Background (CMB), providing support for the idea that the Universe underwent a period of inflation.
In some ways, these were baby steps on the route to understanding the Universe. The real leap came from lesser-known hardware with an awkward name: the Wilkinson Microwave Anisotropy Probe, or WMAP. By giving us the first detailed look at the CMB, WMAP answered everything: the age of the Universe, what it’s made of, its geometry, and more.
Over the weekend, the team behind WMAP was honored with the Breakthrough Prize in Fundamental Physics, which gave us the opportunity to talk to one of its lead scientists, Princeton’s David Spergel.