3 ms·
For life to emerge in the span of a few million years within liquid interiors of early solar system bodies, life would need to be a relatively high probability
by gradus_ad 2y ago
For life to emerge in the span of a few million years within liquid interiors of early solar system bodies, life would need to be a relatively high probability event. I don't think this changes the probability of life calculus vs the traditional life emerging on Earth story.
- pavel_lishin 2y agoIf there were enough of these warm, water-bearing bodies, then the probability could be low and still result in early life formation, right?
- pfdietz 2y agoEspecially if the "enough" is "enough around any star, anywhere". The a priori probability of it happening around any particular star need not be high. And "anywhere" can be something extremely broad, as in "on any branch of a universal Many Worlds wave function".
- gradus_ad 2y agoYes but the window of time during which these bodies could have contained liquid water was very narrow, so there would have needed to be a very high number of such bodies to support the low probability of life hypothesis
- pfdietz 2y agoNo, that's wrong. You're ignoring that if it didn't happen, we wouldn't be here to see the result. Observer selection bias. The less common OoL is, the more biased our observation is.
- gradus_ad 2y agoObserver selection bias is independent of the earth vs non earth body question, it's an issue regardless.
- pfdietz 2y agoYes, it also demolishes the naïve Copernican argument that because life is on Earth, it must be common. The more subtle argument was that because life originated early on Earth, OoL must be a high probability event. But that argument implicitly assumes the probability of OoL is relatively constant with time, so it wouldn't be biased to occur early. OoL on small planetesimals is naturally biased to occur early, due to decay of those short lived radioisotopes. After the planetesimals freeze OoL there doesn't seem possible.
- pvaldes 2y agoOk. What is an Ool?
- superposeur 2y agoI would think this point would be obvious, but apparently not given the many frustrating discussions I’ve had with smart people on the topic. (Maybe there is a subtlety I’m not appreciating?) It’s a relief to see the good solid sense in all your comments on this thread.
- marcosdumay 2y agoUnless life can only appear on that kind of environment for some reason. It's hard to imagine any such reason. Honestly I don't think there's any to find. But it's still an open question.