Vincent Vennin

The early universe expanded at an unimaginable rate — faster than light could cross it. In this boiling cauldron, any region of space resembled an open can of paint: its boundaries continuously captured new 'vapor' from outside, while some of its own contents irrevocably escaped.

After the Big Bang, the universe underwent a rapid expansion — inflation, smoothing out the cosmic microwave background and sowing the seeds of galaxies. But at the quantum level, chaotic fluctuations brewed in the inflaton field.

Inflation is the rapid expansion of the newborn Universe, when quantum fluctuations were stretched to cosmic scales. The cosmic microwave background is the fossilized light of that epoch, shadows on the wall of our cosmic cave.