There doesn’t have to be a motivation. As you yourself in your own post just admitted, you could get there incrementally. All that is required is that among a pool of technological beings on earth making various probes, some people make probes that are more voracious about self replication than others. If the probes, as they copy themselves, deliberately mutate themselves or self modify…well…you know the results.
Life doesn’t have a purpose, it just exists because it can exist, and it’s only goal is to continue existing and spread itself wherever it can.
The other motivation is a classic one. Let’s say the probes aren’t dumb, they have people smarter than you or I onboard (as digital intelligences, not apes in a can). “All these rules against <some futuristic restriction we wouldn’t understand> suck. I wanna go somewhere the authorities can’t disrupt my flow, mon. Let’s build a starship and blow this joint.”
Eventually, evolution will push towards beings who are just inherently restless and hate staying in a given star system, always wanting to push the frontier further.
I’m not so convinced. I feel like planets are going to start looking pretty much the same after you’ve explored a few million of them. Could well be that there are other dimensions that are more exciting to explore.
My solution for the Fermi paradox is by analogy to the first forms of life.
Once you had life competing with non-life, it filled up all the niches life could fill up. There was no second origin of life because the first origin got there first and used the resources a second origin would need.
On a geologic time scale, a civilization could colonize the entire galaxy in a short span - let’s say 10 million years, which is a speed of just 1% light. And once the galaxy has been colonized by one life form, the resources needed by a new one are already taken.
Conclusion: there can only be one intelligent species per galaxy… and here we are.
This assumes we don’t wipe ourselves out first, but it explains why we don’t see any other aliens. If they were there, we wouldn’t be.
The point is, Martian, that a few million years is an eyeblink. Those “guys”, if they exist, it is vanishingly unlikely that they are at our development level or ahead of it.
Doesn’t change the fact that if there’s a pool of explorers, copying themselves with modifications every generation, some of those explorers won’t get bored and will be perfectly happy continuing to explore our dimension. Same basic natural selection as everything else that led to life.
But we do have a strong motivation to prevent this from happening. We are ethical beings who do not want to see the galaxy destroyed and all those lifeforms extinguished. Self-replicating physical machines are not something somebody can make inadvertently. We would have to deliberately build them at enormous cost and effort. Knowing how incredibly stupid and dangerous that would be, I don’t see why anyone would.
If we were to create a superintelligent AI capable of creating replicator-bots, the issue would be the so called control problem. If its goals are misaligned with ours, then who knows what it might do. Since it would be unlikely to face any competition though (for very long at least) its hard to see how the kind of ‘selection in favour of expansionism’ you describe could come about. Again I would say it would come down to the motivation of said AI overlord. So the ‘paradox’ becomes ‘why haven’t aliens built superintelligent machines which inexplicably want to destroy the galaxy.’
For one thing, it would make us (well, whoever is alive when this is done) immortal, or near immortal (universe appears to be dying but it’s trillions of years away). For another, different people have different ethics. I see nothing ethically wrong with “destroying” the dead matter of the galaxy. I see it as bringing it all to life - you would store on digital data files the original state of all the planets and moons and asteroids you tear down, so it’s not like they are really gone. You would be able to recreate them if you wanted. If you find a planet that actually has life on it, I wouldn’t destroy it, I’d just occupy all the dead rocks in the same planetary system and observe the life non-invasively from a distance.
But your descendants who stopped at converting only the dead matter would be superceded by all-consuming destructo-bots.
Is that what you want? Cos that’s what’ll happen.
Maybe. Maybe not. That’s the other thing. If “I” consume all the ecological niches, there won’t be a niche for the destructo-bots. Also, defending a star is probably vastly easier than attacking it - any starship decelerating has to emit a flare of gamma rays as bright as a star to run the matter conversion drive you have to use. (by matter conversion I just mean a catch-all term for fusion, antimatter, or even black holes. Some way of burning matter for energy).
So you can see them coming, and the payload on a starship has to be small and light, or it would have required too big of a rocket to launch. So you just send out a “who goes there” radio message and zap em with a big x-ray laser if you don’t like the answer.
It would be like postulating that Columbus-the-Italian is crossing the Atlantic, and just happens to run into Columbus-the-Aztec halfway across. The odds that one of them is not first are just insignificant even on a galactic scale.
Not in my experience. Once you take down the Dyson sphere, they’re pretty much sitting ducks. Send in the nano-swarm to clear the area, then a massive EMP to disable them and it’s job done. Lovely matter for supper.
Wait but why did a good article on the Fermi paradox discussing this scenario, where there could be a massive bottleneck after a society develops technology but before they become inter planetary or inter stellar.
Here is a good video too.
Even if FTL travel is not possible, we can still colonize the galaxy in a couple million years which isn't very long on a universal scale.
Maybe there is a technological civilization out there somewhere, and we haven’t seen them because they have no interest in leaving their home planet. The assumption that any technological civilization will eventually take to the stars may not be valid.
It’s not, because we’re nowhere near beginning to cross the cosmic Atlantic. We may never do it. It’s like Columbus the Italian staring out over the ocean trying to spot something over the horizon, and Columbaztek doing the same on the other side.
I aliens are looking in our direction, chances are that they’re not noticing us. Same for the other direction.
Sure, but there are various processes along the way that take a long time. On Earth, IIRC, to go from very simple proto-cells to the first multicellular life took over 3 billion years.
Perhaps this is an astonishingly quick time for a whole series of unlikely events to happen, and Earth is indeed first out of the block.
Yes, but as far as I know, the voyager plaque does not attempt to turn all of the matter in the galaxy into little plaques. Building self-replicating, galaxy colonising robots and firing them off in all directions is way beyond our technology for the foreseeable future. If it wasn’t, it would be irresponsible and dangerous beyond belief.
Maybe the answer to the supposed paradox lies in the anthropic principle. We know we are in a galaxy where there has only been one technological species, because in galaxies with multiple such species, sooner or later, somebody has the monumentally dumb idea of releasing self-replicating robot colonists all over the place. We therefore would not exist if anyone had gotten there significantly before us.