The Habitable Epoch of the Early Universe

That gets into astrobiology. Theoretically life could have started as soon as its basic ingredients were ready. So not until things had cooled down a bit after the Bang, when there were heavier elements than hydrogen and helium; and some kind of land and water. > In the redshift…

lioetersNov 27, 2025View on HNParent context

my favourite hypothesis for the first life is the idea that the entire universe might have been habitable for a while: https://arxiv.org/abs/1312.0613 of course, it's very unlikely, but it's such a cool idea!

exe34Feb 3, 2025View on HNParent context

> the time when the universe was at life supporting temperatures, was long before the formation of the first stars and fusion of heavier atoms than hydrogen Stars with rocky planets during the habitable epoch "lie ∼8.5 standard deviations (σ) away on the exponential tail of the…

JumpCrisscrossJan 28, 2024View on HNParent context

https://arxiv.org/abs/1312.0613

umeshunniAug 30, 2023View on HNParent context

This reminds me of a paper [1] where they find that... "In the redshift range 100<(1+z)<137, the cosmic microwave background (CMB) had a temperature of 273-373K (0-100 degrees Celsius), allowing early rocky planets (if any existed) to have liquid water chemistry on their surface…

negativelambdaJan 5, 2023View on HNParent context

The big bang was extremely hot; the universe now is quite cold (microwave background). It was a continuous process of cooling, implying that there was an interval where the entire universe was comfortable (there are at least a few papers on this, e.g.…

jonah-archiveApr 30, 2022View on HNParent context

I did my PhD in astrophysics, and I can tell you that the author's name has become synonymous with, shall we say, fringe ideas. I won't say crack pot because he is a legit tenured astronomer at Harvard, but I have seen his papers roundly critiqued on the merits at too many…

ahwvd37jsMay 26, 2021View on HNParent context

Regardless of the truth in this specific case, Avi has some very interesting ideas such as the habitable early universe. https://arxiv.org/abs/1312.0613

hchzJan 20, 2021View on HNParent context

Maybe life originated during the habitable epoch in the very early, very small universe and spread from there? https://arxiv.org/abs/1312.0613

thearn4Jan 19, 2021View on HNParent context

The habitable epoch of the early Universe, Abraham Loeb, DOI: https://doi.org/10.1017/S1473550414000196 https://arxiv.org/abs/1312.0613 , https://www.cambridge.org/core/journals/international-journa... >"In the redshift range 100≲(1+z)≲137, the cosmic microwave background (CMB)…

superkuhDec 27, 2019View on HNParent context

It is a pretty out there theory, but at one point the universe would have cooled enough from the very hot big bang origins to allow liquid water to exist everywhere, but not cooled sufficiently to cause everything to freeze. If any rocky planets existed at the time, maybe that…

throwaway2048Jul 10, 2019View on HNParent context

This reminds me of "The Habitable Epoch of the Early Universe" https://arxiv.org/abs/1312.0613 where it is pointed out that for some time during cosmological evolution, the universe would have been quite comfortable and rocky planets (if any existed) could have had liquid water…

evanbApr 20, 2019View on HNParent context

This has received some serious consideration in Loeb's "The Habitable Epoch of the Early Universe" https://arxiv.org/abs/1312.0613

evanbOct 14, 2018View on HNParent context

Let's not forget about the habitable epoch of the early universe [1]. There's a good 7 million years near the beginning of the universe that in principle was inhabitable to Earth-like life. None can say if the physicists of that epoch (if there were any) had enough observational…

evanbJul 28, 2015View on HNParent context