In the redshift range 100<(1+z)<110, the cosmic microwave background (CMB) had a temperature of 273-300K (0-30 degrees Celsius), allowing early rocky planets (if any existed) to have liquid water chemistry on their surface and be habitable, irrespective of their distance from a star.
In the standard LCDM cosmology, the first star-forming halos within our Hubble volume started collapsing at these redshifts, allowing the chemistry of life to possibly begin when the Universe was merely 15 million years old.
The possibility of life starting when the average matter density was a million times bigger than it is today argues against the anthropic explanation for the low value of the cosmological constant.
Abraham Loeb (Harvard) (Submitted on 2 Dec 2013)
Comments: 6 pages, submitted to Astrobiology
Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO); Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:1312.0613 [astro-ph.CO]
(or arXiv:1312.0613v1 [astro-ph.CO] for this version) Submission history From: Avi Loeb [v1] Mon, 2 Dec 2013 21:00:18 GMT (6kb)
Please follow Astrobiology on Twitter.