A list of solutions to the Fermi Paradox

As Tim Urban says, ‘We’d estimate that there are 1 billion Earth-like planets and 100,000 intelligent civilizations in our galaxy.’ So there must be aliens. Why haven’t we heard from them? (Read about the Fermi Paradox here.)

This blog is a list of answers. I’ve summed up each one in a line and dropped a relevant quote afterwards, and mostly linked to an article not a paper. Some of the ideas overlap or are sub-categories of each other. I tried to avoid an endless list, but still give different perspectives.

List of possible solutions to the Fermi Paradox

We don’t seem to have got much beyond this list of categories of answers from ‘Extraterrestrial Intelligence: Where is Everybody?’ by John A. Ball, which was written in 1985.

I’m naturally sceptical, and it might be bad news if there are aliens, but as Tyler Cowen says, ‘when you run all the arguments through your mind, is it not possible to come away with an estimate of at least a one-in-a-thousand chance that alien visitations are a real thing? ‘

p.s. After I finished this post, I found this list of ‘50 solutions to the Fermi Paradox‘ (based on a book about the same thing by physicist Stephen Webb). That list is not all brilliant (mine is closer to what I wanted to read but couldn’t find) but it is fairly comprehensive without too much chatter. I haven’t read the book.