Maybe they're sleeping?
Fermi's paradox asks the question: why haven't we found or discovered any intelligent extraterrestrials despite the overwhelming probability that they do exist?
Many theories have been proposed as to why that is, and people could spend their entire lives trying to figure out why, but some reasons that a lot of people think this is the case are: We are infact alone, intelligent life plateaus at a certain point, or alien life does exist but they are too primitive.
Now, some researchers have come up with a new theory in their latest research paper. They claim that the universe is "too hot" right now for advanced and digital civilizations to make use of their resources and thus their solution is to "sleep" and wait for the universe to cool down in a process they call "aestivating."
An interesting idea. But I highly doubt that this is THE explanation for the Fermi Paradox, or even a particularly important part of the puzzle. Among other obvious flaws, it posits an implausible degree of uniformity among these advanced societies.
Moreover, even if their machinery would work more efficiently when the universe cools down, it makes little sense to completely forego nearly all activity until that happens billions of years from now. They could get at least some "work" done in the interim, and losing huge amounts of time is itself a massive inefficiency.
Of course, maybe they just don't care about efficiency and/or loss of time. But in that event they wouldn't care so much about inefficiency caused by heat, either. At the very least, the combination of preferences needed to get this outcome (great concern about inefficiency caused by heat, virtually no concern about inefficiency caused by loss of billions of years of time) seems highly unlikely to be universal.
