New Theory Concludes That the Origin of Life on Earth-Like Planets Is Likely:
Does the existence of life on Earth tell us anything about the probability of abiogenesis — the origin of life from inorganic substances — arising elsewhere? That's a question that has confounded scientists, and anyone else inclined to ponder it, for some time.
A widely accepted argument from Australian-born astrophysicist Brandon Carter argues that the selection effect of our own existence puts constraints on our observation. Since we had to find ourselves on a planet where abiogenesis occurred, then nothing can be inferred about the probability of life elsewhere based on this knowledge alone.
[...] However, a new paper by Daniel Whitmire, a retired astrophysicist who currently teaches mathematics at the U of A, is arguing that Carter used faulty logic. Though Carter's theory has become widely accepted, Whitmire argues that it suffers from what's known as "The Old Evidence Problem" in Bayesian Confirmation Theory, which is used to update a theory or hypothesis in light of new evidence.
[...] As he explains, "One could argue, like Carter, that I exist regardless of whether my conception was hard or easy, and so nothing can be inferred about whether my conception was hard or easy from my existence alone."
In this analogy, "hard" means contraception was used. "Easy" means no contraception was used. In each case, Whitmire assigns values to these propositions.
Whitmire continues, "However, my existence is old evidence and must be treated as such. When this is done the conclusion is that it is much more probable that my conception was easy. In the abiogenesis case of interest, it's the same thing. The existence of life on Earth is old evidence and just like in the conception analogy the probability that abiogenesis is easy is much more probable."
Journal Reference:
Daniel P. Whitmire. Abiogenesis: the Carter argument reconsidered [open], Int J Astrobio, 2022. DOI: 10.1017/S1473550422000350
(Score: 2) by Immerman on Thursday October 06 2022, @05:46PM (2 children)
And when did it emerge there?
(Score: 2) by legont on Friday October 07 2022, @12:25AM (1 child)
Perhaps, even before the big bang.
"Wealth is the relentless enemy of understanding" - John Kenneth Galbraith.
(Score: 2) by Immerman on Friday October 07 2022, @03:44AM
Not unless it's high tech enough to have hopped into the universe from elsewhere hundreds of millions of years after the big bang - prior to that the universe was too hot for atoms to exist. And if you're hopping universes, then you run into the problem that there's absolutely no reason to believe the laws of physics are the same between any two universes. It's quite possible that out of an infinite number of universes, this is the only one in which atoms as we know them can exist. Kind of hard to colonize another universe when your constituent atoms cease to exist upon entering.
And even assuming it's possible - all your insanely magi-science equipped universe-hopping aliens have accomplished, from our perspective, is to push the origins of life back a little. At some point in the past life had to emerge from somewhere - unless you want to argue that life somehow predates not just our universe, but all of existence? And... that's a bit of a problem, as it certainly seems that life has its roots in physical reality.