Currently, panspermia has been rated as “plausible but not convincing.” Marks, Hössjer, and Diaz discuss the issues:
Robert J. Marks:Isn’t the idea of panspermia just kicking the can down the road? It’s just kind of displacing the problem of where we came from to, “Where did this incredible civilization come from?” The planet life here on earth.
Daniel Díaz: Recently, there was a debate, a conversation between Sabine Hossenfelder, a very famous physicist with well-known channel on YouTube and Luke Barnes, who has done extensive research on fine-tuning.
They coincide in explaining why fine-tuning is actually not a scientific question. So Luke Barnes said that basically science ends saying that there is fine-tuning. Of course, different world views are going to produce different explanations for that fine-tuning that we are observing in nature.
Robert J. Marks: Interesting. Panspermia, again, kicks the can down the road. It leads the question as to the origin of this master people that came here and planted life on earth. It’s just strange. News, “Is life from outer space a viable science hypothesis?” at Mind Matters News
Here’s a video debate between Sabine Hossenfelder and Luke Barnes. (2021). Also available as a podcast.
Takehome: Famous atheist scientists have favored panspermia because there is no plausible purely natural explanation for life on Earth that would make it unnecessary.
Here are the previous instalments of the discussion of fine tuning for life::
The first episode:
Ours is a finely tuned — and No Free Lunch — universe. Mathematician Ola Hössjer and biostatistician Daniel Andrés Díaz-Pachón explain to Walter Bradley Center director Robert J. Marks why nature works so seamlessly. A “life-permitting interval” makes it all possible — but is that really an accident?
and
Fine-tuning? How Bayesian statistics could help break a deadlock Bayesian statistics are used, for example, in spam filter technology, identifying probable spam by examining vast masses of previous messages. The frequentist approach assesses the probability of future events but the Bayesian approach assesses the probability of events that have already occurred.
The second episode:
Life is so wonderfully finely tuned that it’s frighteningA mathematician who uses statistical methods to model the fine tuning of molecular machines and systems in cells reflects…
Every single cell is like a city that cannot function without a complex network of services that must all work together to maintain life.
Can there be a general theory for fine-tuning? If you make a bowl of alphabet soup and the letters arrange themselves and say, good morning, that is specified. What are the probabilities? Ola Hössjer sees the beauty of mathematics in the fact that seemingly unrelated features in cosmology and biology can be modeled using similar concepts.
The third episode
Was the universe created for life forms to live in? How would we know? We can begin by looking at the fundamental constants that underlie the universe. The constants of the universe — gravitational constant, entropy, and cosmological constant — must be finely tuned for life to exist.
Why did Stephen Hawking give up on a Theory of Everything? Daniel Díaz and Ola Hössjer continue their discussion of the fine tuning of the universal constants of nature with Robert J. Marks. The probability, they calculate, that the fine tuning of our universe is simply random is down to 10 to the minus sixty — a very small number.
You may also wish to read: No Free Lunches: Robert J. Marks: What the Big Bang teaches us about nothing. Bernoulli is right and Keynes is Wrong. Critics of Bernoulli don’t appreciate the definition of “knowing nothing.” The concept of “knowing nothing” can be tricky.
The first part of the fourth episode
Is life from outer space a viable science hypothesis? Currently, panspermia has been rated as “plausible but not convincing.” Marks, Hössjer, and Diaz discuss the issues. Famous atheist scientists have favored panspermia because there is no plausible purely natural explanation for life on Earth that would make it unnecessary.