Why were galaxies so active in the early universe? We may be getting close to the answer

The James Webb Space Telescope deep field image showing some of the earliest and most distant galaxies ever seen.

In its infancy, the universe had a bit of an identity crisis.

For the first few hundred million years, the vast cosmic gas between galaxies was primarily a chilly, dense affair. But then, it seemed to wake up, deciding to get all warm and fuzzy.