Oct 23 2023
Panspermia Again
Recently I was asked what I thought about this video, which suggests it is possible that life formed in the early universe, shortly after the Big Bang. Although no mentioned specifically in the video, the ideas presents are essentially panspermia – the idea that life formed in the early universe and then spread as “seeds” throughout the universe, taking root in suitable environments like the early Earth. While the narrator admits these ideas are “speculative”, he presents what I feel is an extremely biased favorable take on the ideas being presented.
The video starts by arguing that life on Earth arose very quickly, perhaps implausibly quickly. The Earth is 4.5 billion years old, and it likely cooled sufficiently to be compatible with life around 4.3 billion years ago. The oldest fossils are 3.7 billion years old, which leaves a 600 million year window in which life could have developed from prebiotic molecules. When during that time did these complex molecules cross the line to be considered life is unknown, but it seems like there was probably 1-2 hundred million years for this to happen. The video argues that this was simply not enough time – so perhaps life already existed and seeded the Earth. But this argument is not valid. We do not have any information that would indicate something on the order of 100 million years was not enough time for the simplest type of life to form. So they set up a fake problem in order to introduce their unnecessary “solution”.
But the argument gets worse from there. Most of the video is spent speculating about the fact that between 10 million and 17 million years ago the temperature of the universe would have been between 100 C and 0 C, the temperature range of liquid water. During this time, life could have formed everywhere in the universe. But there is a glaring problem with this argument, that the video hand-waves away with a giant “may”.