Was the early universe a better environment for life to evolve?

Harvard astronomer Avi Loeb has just published a paper about how life might have flourished when our 13.8-billion-year-old universe was a mere 15 million years old. Back then, the whole universe was warmer — which means liquid water could exist even on planets that were distant from their stars.

Writes Loeb in the abstract for the paper:


Though we often think of the early universe as inhospitable, Loeb notes that if rocky planets existed, it would have been a great time to live on them. No matter where they were in the universe, they would have been bathed in constant warmth, with no need to depend on a star for energy. And the warmth would have made surface water a liquid, too, which would help life as we know it to develop.


Of course there is that little matter of matter density being "a million times bigger than it is today." Hard to say whether that would be a problem or not for the development of life. It certainly would have made our view of the heavens a lot different, and brighter.

The sad part about contemplating Loeb's idea is that it makes you wonder whether the universe was teeming with life back then, and we're merely the sad outliers who happened to evolve in the post-life era. All our potential friends in the universe might have lived (and eventually died out) billions of years ago.

Read the whole paper at Arxiv.

Thanks for the tip, Warren Siegal!