|>> || |
I think when we are reasoning about something no one has ever seen any evidence of (ETI) we are inherently making fact-less assumption. The whole concept of the Fermi paradox rests on a number of assumptions which may be false. When we're talking about a set of assumptions, none of which have strong facts to connect to them, I think the only way to distinguish the quality of the arguments is how many inductive reasoning principles they agree. The second we get a shred of hard evidence, all this is naturally out the door.
Here's my argument for why I think the Zoo hypothesis is the best explanation for the Fermi paradox (I know that's not exactly what you asked but should cover it.) It's mostly by exclusion of the other possibilities with a few other facts thrown in.
>Other solutions to the paradox -too few planets, too few main sequence stars: discounted by modern astronomical evidence
-rare earth, too many conditions needed for abiogenesis: mostly informed by 19th century theories about how life started, we now know life has multiple possible streams of development (from the shift to the thermal vent theory from the 'primordial soup' theory)
-there hasn't been enough time yet: discounted by our improved knowledge of the age of the universe and the physics of star system formation
-intraspecies or interstellar apocalyptic wars: maybe, but we would probably see evidence of this, so the fact that we don't means if this is the case it probably must also exist with the Zoo hypothesis in place. Also, if such things routinely happened in the galaxy often enough to keep all theoretical interstellar civilizations tamped down, it would have to happen at least every couple of million years -- I would think. Maybe they just haven't gotten around to stamping us down in the million or so years we've been an intelligent species, but it seems unlikely.
-natural apocalyptic catastrophes: If we have gotten this far and not yet been zapped by a gamma ray burst, there's no reason to think that no other species would be able to make it to space travel before getting zapped.
-scarcity, not enough resources: bollocks. The galaxy is so completely full of more stuff than any one species could ever need its absurd to think this.
-listening to EM radiation is wrong: I think this is a strong candidate if we someday discover our physics is incomplete and tachyonic communication is somehow possible. Any interstellar civilization would be dependent on this form of communication, so if it exists its reasonable to think most if not all theoretical ETIs we would search for use it exclusively. This also may feed into the Zoo hypothesis; they are able to keep us completely blind to them because they understand physics we do not, which certainly seems likely.
So taking that all in, we are left with the basic fact of the Fermi paradox that by all accounts life should be everywhere, and should be much older and more advanced than us, and have had millions of years of head start setting up a galactic civilization. Such beings would naturally have more advanced science and technology. It is the height of human arrogance to think that simply because we cannot conceive of a way our senses could be fooled they could not be; a pet ant has no way to conceive that it is trapped in a farm, yet it is. By all its senses and understanding, everything is just as it should be.
Moreover, I think the reason that any interstellar civilization would come to a consensus on how to manage less developed civilizations and impose it on a galactic scale, is not because we are special, or to protect us from harm, but simply to protect themselves from us. Interacting with a more primitive species invariably destroys the existing native culture and leads to a situation where they will try to steal the more advanced culture to overthrow the power relationship. Simply leaving them alone allows them to develop potentially galaxy destroying technologies like Von Neumann probes or otherwise wrecking environmental havoc, perhaps precisely by kooky megastructure concepts. So, from a game theory perspective, I think most species would converge on the idea that the safest thing to is to keep primitive species ignorant of the galaxy at large until they have developed to the point that they can discover it on their own, i.e. they've reached a level of technological and cultural maturity where they can at least comprehend why they have to cooperate with the rest of the galaxy, because of the extreme existential threat posed by the kinds of technology such K2+ civs would wield.
So anyway, why no megastructures and a pristine universe beyond? All they would have to do is intercept photons in a radius around the solar system and modify them slightly, they might not have much work to do if ETI mostly uses FTL comms. Sounds like a massive undertaking for us but for a Kardashev III civ a nanodust of self replicating light sensors and laser transmitters dispersed in the Oort cloud of any star that has the potential of developing sentient life would be trivial, like mulching the garden. They don't do it because we are special or they love us (they might, they might not) but mainly because all 'civilized' life recognizes the 'primitives' as dangerous and both wants to keep them at bay, and keep them from wanting to take the goods of civilization, thus tabs need to be kept on them. Factor in the level of existential threats advanced technology can create and to me it seems like it would be viewed as a logically necessary solution for any species that got to the level to be able to do it.
>>There's a lot of things our unlikely moon helps our world withI didn't say it didn't help, just that it wasn't strictly necessary for life to form, as was a popular hypothesis in the 20th century. Also if I recall correctly the theory about the moon helping the core remain liquid was proven false because of the scales involved, and had been thought due to Mars' lack of large moon and solid core, but our core is liquid because of its greater mass. Could be wrong about that tho.