One of the professors in my department when I was a grad student in astronomy was a vegetarian because of the Fermi Paradox. His reasoning was that intelligent life probably doesn't exist anywhere else in the universe and so a chicken is one of the most intelligent life forms in the universe. And given ~100 million years of evolution it could even become as intelligent as a human. Another professor I knew thought that the Fermi Paradox implied that interstellar space travel was probably too difficult an engineering problem to ever be solved.
I got the sense that a lot of astronomers (though probably not a majority) have strong opinions about the Fermi Paradox, but they only rarely discuss them. It's one of those weird problems where there's some data --- enough to reason out some conjectures --- but not enough to really make any definitive conclusions. But because the answer you end up with has such profound consequences you feel obligated to at least try to make the most of the little data you have. I guess in Bayesian terms, it's one of those situations where the priors you put in basically determine the answer you get out --- if you disagree about the priors, you'll disagree about the conclusions.
I really enjoy Isaac Arthur's videos on the subject (he has a playlist with several hours of content exploring different possible solutions). The rest of his channel is great too; he posts a new 30-60 minute video every Thursday.
Issac Arthur has his stuff together. His videos are for the most part well researched and contain a lot of interesting hard sci-fi ideas. The only time I've seen him fall down is his video about quantum computing, but to be fair, a lot of people get caught by the same mistake. It's not the case that a quantum computer is trying out all of the bit-strings that are possible answers in a kind of quantum-superposed parallel computing. That's not exactly what is happening.
One of the key insights: Qubits store complex numbers!
I have a two comments to share about this paradox.
1. The assumption that there are many advanced ET civilizations in the universe is based on the idea that life emergence is a natural and random process. This has not yet be proven to be valid. I share this opinion, but it is important to be aware of the underlying hypothesis because this is what can invalidate the claims.
2. The other point is the "we don't see them". There is also an underlying hypothesis that ET manifestation would be ostensible. Many people deduce from this that they are not on earth and start to speculate on different reason for that.
The hypothesis that ET do not visit us is really not so sure. The first reason is that this visit and exploration may not be in the form we expect (e.g. colonization, diplomatic) and not directly visible to us (e.g. Spying, non-interfering scientifc study). The other reason is that they might have been visible for decenies as UFOs and third type contact encounter. But this possibility is rejected, and had been rejected by Enrico Fermi. To me this is the only paradox in the Fermi Paradox.
However, I do agree that if UFOs are visible ET manifestion on earth, this manifestation has puzzling and unexpected properties. The strongest one being that they apparently seem to leave us alone. There is currently no way for us to know why and deduce anything from this, like for instance rejecting the UFO phenomenon as possible ET manifestavtion because their behavior doesn't match our expectation.
To be more accurate, the report of UFO sightings dropped significantly after the eighties. The other weird property is an increase in UFO sighting after the second world war. Jean Jacques Velasco (GEPAN) suggested that it was correlated with nuclear explosions on earth. This is nonetheless suprizing because it would imply that they can make interstellar travels at a very high speed. We currently don't know how this is possible.
Anyway, we have to be careful to not consider a behavior not matching our expectation as a reason to invalidate the phenomenon because it is our expectations that may be invalid.
The problem is not that we do not see them. It's that we exist, so they didn't use every star system on the galaxy to build some swarm brain, giant living surface, or whatever before we even had a chance to be.
Not sure why you were down-voted. Isaac Arthur's perspective is that a species with the opportunity to expand would turn ever star into a Dyson swarm which, in turn, would darken the stars. If ET existed, the night sky would be dark.
Why would they? Using stars for energy is a human-scale idea.
The majority of alien-scale ideas are likely unimaginable in our current state of development. Trying to imagine them is like trying to build a Haskell compiler out of rocks.
Indeed. Our expectation that ET would have an interest in colonizing planets may be wrong. With a space vessel, they would have a perfectly adapted and mobile environment. They can avoid danger and explore to accelerate their technological and scientific evolution.
We are still rooted on the ground like vegetals while they could move freely like animals.
Yes, it assumes that. To put it fairly, every other species on Earth is expansionist, and ours has still expansionist subgroups that, if things keep going this way, will take over he rest of the population in a couple of centuries.
My gut instinct tells me we're not special enough to be the only intelligent life out there. We humans have reliability had our egos crushed over and over again as we learned that we are not the center of the solar system, nor the only galaxy, etc, etc.
I think it's way more likely the universe is teeming with intelligent life, but in dimensions that we're not evolved enough to comprehend or sense, and the thought that we are alone is laughable from the point of view of the "aliens".
Hell, we don't even have the faintest idea of how our own brains work, why we need to sleep, and all kinds of other things. To even believe for an instant that we are so special that we're actually alone in the entire universe or even the galaxy is a bit ridiculous.
The fact that it's ridiculous is precisely why it's a paradox. Some aliens may be evolving on different levels as you say, but all of them? Your resolution is they are there but we can't see any of them or their effects.
It could well be that the exponential advancement in technology makes it so there is only about a 100 or 200 year gap where civilizations send out radio waves, or whatever our current technology is capable of receiving - before hitting these other dimensions.
But even so, there would still be a chance to detect this kind of stuff. I mean, I totally see your point - I just don't think we're that special though.
There could be no greater irony: For all the sublimity of art, physics, music, mathematics and other manifestations of human genius, everything depends on the mundane, frustrating, often debased vocation known as politics.
I got the sense that a lot of astronomers (though probably not a majority) have strong opinions about the Fermi Paradox, but they only rarely discuss them. It's one of those weird problems where there's some data --- enough to reason out some conjectures --- but not enough to really make any definitive conclusions. But because the answer you end up with has such profound consequences you feel obligated to at least try to make the most of the little data you have. I guess in Bayesian terms, it's one of those situations where the priors you put in basically determine the answer you get out --- if you disagree about the priors, you'll disagree about the conclusions.