And practically will be, by the time it ever becomes possible. Everything can’t be built and launched from Earth.
Even worse, as I indicated upthread, there’s “Earth-like”, as in the distant past, and “Earth-like” as she is now. The former should more properly be called “Earth-potentials”. Unless native life has ALREADY terraformed the atmosphere like ours has here, so that a sustained breathable O2/N2 air mass is already available, those nanoprobes will have to do the terraforming themselves, which would indeed include seeding the surface with suitable life forms to redo and sustain the atmosphere. Is it even possible to have a substantial O2 atmosphere (with a suitable inert partner like nitrogen) which is self-sustaining via NONbiological means?
Yeah, some of the issue seems to be that either there’s a barren planet with an atmosphere humans can’t breathe, or there’s (maybe, we don’t know) a planet with an atmosphere we can breathe — and its own well developed ecosystem; which, even aside from moral questions about our screwing it up, may well also be deadly to humans.
Maybe we’d eventually have probes that can go there; maybe not. But for us to go there in any numbers, even aside from transport problems, is another thing entirely.
If we ever find a planet with a complex biosphere we should treat it as precious, and resist any attempt to colonise or otherwise damage it. Each world of this kind has the potential to eventually evolve something as complex as (or more complex than) human civilisation, but from a different starting point - so we should leave well alone.
Life - especially, but not confined to, complex life - is probably the most valuable thing in the universe.
I admitted as much in my post. I was using that graphic to show immensity of our galaxy. The Voyager probes are not slow. A standard 308 rifle bullet travels about 1800 miles an hour. The probes are going about 38,000 miles per hour. I meant to show that after a million years at that speed, we would still be in our neighborhood.
This is sort of irrelevant. If we are going star-hopping, a SRP will need to be able to achieve escape velocity of the local solar system. If you can barely make it of off an asteroid, you are not going to be colonizing other star systems.
And space fairing vehicles are not made primarily of iron.
A self-replicating probe will need to be made up of 4 main sections - a space ship (a housing to encapsulate the whole with an engine of some sort to transport all of the components), mining component to dig out raw materials, fabricating component to turn the raw materials into parts and an assembly factory where it will all be assembled.
To think of building all of the connecting parts, the glass, plastics, sheet metal, aluminum and mixed metals, navigational instruments, plutonium-238, thermoelectric generators, and hundreds of more parts is just asking too much from a robot. It would require a colony of humans basically starting from scratch and replicating the infrastructure we have on earth.
The actual noob mistake is assuming we will have SRP ever. Heck, we have been trying build self-replicating machines/robots for decades and have gotten nowhere - and they don’t even have to go to space or visit other stars.
The “noobs” includes pretty much every prominent physicist, aeronautics engineer and futurist that has ever written on the topic.
I think part of the issue here is that in daily life, any theoretical technology that is not going to be feasible in our lifetime, or even our children’s lifetime, is crazy pie-in-the-sky stuff that is basically not worth our time talking about.
That’s fine, but the context of the fermi paradox is quite different, because there is the possibility of intelligent species persisting over deep time.
In this context, it’s just irrelevant talking about practical / engineering challenges. We’re talking about what looks difficult to us after one generation in space when we’re talking about species that may have spent millions of generations advancing this tech.
So, in this context, it’s physical impossibility or bust. And frankly, even many things that we think are impossible will look quite different to a deep time species, but we need to at least start there.
Or suggest that no species ever makes it to deep time, in which case that is the filter, not the challenge of making an srp.
I’m quite content to be proven wrong, but I haven’t heard any of them definitively say they believe that. It’s more in the context of ‘if we develop SRPs that can travel at (some percentage of c), then we could colonize the galaxy in 10 million years’.
Note also, that when it comes to theoretical engineering, their guess might not be better than mine. We have made exactly zero headway to date in developing SRPs. In fact I’d say that the fact that no one is even working on one says a lot about their confidence. By contrast, some fantastical machines have not only been thought up, but intricate plans drawn up for, Project Daedalus, for example.
But I’ll read a cite that several aeronautics engineers have said they believe will have SRPs in the future, if you provide them.
We know that self-replicating machines are possible because every organic cell is one. And it doesn’t require some special life-force magic to work; John Von Neumann worked out the logical structure of a self-replicating mechanism in the 1940s. At this point it’s a question of implementation.
I suppose I did misspeak.
We have the knowledge of how hard, how long, and where to push to get us to the stars. That’s quite unlike 30,000 years ago. We also have industrial society capable of large-scale engineering.
However, we’re using interstellar travel to mean expansion of our species into space, aren’t we? That means we have to go fast enough that we’re not just indulging in astronomically expensive space burials. Or if it’s going to take thousands to tens of thousands of years to reach another star, we’re going to have to develop some form of artificial life. Are we appreciably closer to achieving that than we were in the Paleolithic?
The project Lucas_Jackson mentioned a few posts up is a gigantic (seriously, just look at the Saturn V next to it) New Horizons. It’s a one way trip out of the galaxy with a fleeting flyby of one star system. Even that amounts to throwing a bigger, fancier, much more expensive rock into the cosmic sea.
I’d say we are closer to creating artificial life than making starships or self-replicating systems. Biotechnology will continue to advance, even though we reach hard limits in the acceleration and shielding necessary to cross interstellar distances.
At the risk of repeating myself, there are a number of strategies that could allow the transfer of mindkind from star to star; among these are the Sleeper Ship, the Generation Ship, the Methuselah Ship and the Data-only Ship. All of these strategies assume significantly advanced biotechnology of various kinds; most probably the strategy that could be made to work would be a hybrid of all four - a Hybrid Ship, using long-lived biological entities probably in some sort of hibernation, carrying with them the comprehensive genetic databanks necessary to reboot a biological civilisation, and supported by competent artificial intelligences.
The people that go to the stars won’t be like Jim Kirk or Dan Dare, or like us; they will have been re-engineered by hundreds or thousands of years of biotechnology to allow them to survive the journey and thrive on arrival. We will be almost completely artificial by then.
Physicists and engineers are not in the game of saying “if we had magic tech then…” otherwise they could just say “If we had magic teleportation powers then we could visit every planet”.
But anyway, no, people like Freeman Dyson, Frank Tipler, Robert Freitas etc have explicitly said it is a feasible technology. Who do you have in mind that have espoused your position?
bangs head against wall
Firstly, yes we’ve made significant progress. The entire space programme has happened within a human lifetime. We’ve gone from never having left our atmosphere to having landed a probe on an asteroid in that time. You can scoff at this progress (I wouldn’t; I think it’s astonishing) but it’s disingenuous to call it “zero”.
Secondly, who cares how much we’ve achieved in decades or if it seems commercially viable now? I keep talking about deep time, and you keep responding as if I had said 10 or 20 year’s time.
We talk about going from the first powered flight to standing on the moon in 65 years. That’s amazing, and certainly incredible progress.
However, the first powered flight was made possible by 2 guys in a bicycle shop and the moon landing was the culmination of a multi decade effort by the world’s largest economy employing about 400,000 people and 20,000 various businesses and universities.
These tasks aren’t getting easier, they’re getting harder. Building and launching an SRP is going to be orders of magnitude harder than the Apollo Program, and that SRP is going to enter another solar system with nothing but the ability to replicate itself. It will then have to build the production capacity of a small country out of a star system that has spent a billion years approaching equilibrium.
I would call progress a solar powered autonomous robot that could roll into a garbage dump and roll out carrying a 1kg bar of commercial grade 1095 steel. That would be progress towards doing one of the most basic steps of having an SRP. Do you think we have the technology to build something to complete those tasks, in a space smaller than a house? That’s just to consolidate one type of raw material, from pre-made raw materials.
Bang your head against the wall all you want, that doesn’t prove your point, cites will.
Speaking of disingenuous, you have taken my point out of context. I think what we have done with the space program is astonishing. I never scoffed at our space program’s progress. I said we have not made any progress in producing self-replicating probes, and we haven’t.
Building and sending ever-better far flung rockets into space doesn’t equal ‘someday we’ll have SRPs’. They are two different technologies - one doesn’t necessarily follow the other.
Freeman Dyson proposed the concept of self-replicating robots for space exploration and industrial development. He did so as part of a thought experiment, rather than a prediction that we will imminently have them on Earth in a common context. He proposed them as how to approach engineering problems differently, not necessarily a definitive prophecy of their arrival in our everyday lives.
Frank Tipler said that if extraterrestrial intelligence existed, the galaxy should be teeming with von Neumann probes (self-replicating probes) that would have been observable by now. He argued that these probes could colonize the entire galaxy in a relatively short period, a few hundred million years, given even moderate replication rates. Since we have not found any evidence of them, Tipler concluded that we are likely the only intelligent species in the universe, which provides a potential resolution to the Fermi Paradox. He said nothing about how these could or would work. He was basically using these hypothetical machines to bolster his idea that we were alone.
And, of course, Tipler’s ideas were famously countered by Carl Sagan and William Newman.
So you have two competing hypothesis’
- All advanced civilizations develop self-replicating probes - but we don’t see them therefor there is a paradox.
- Or, we don’t see them because there aren’t any.
I wonder what Occam would conclude?
1/ Nobody is saying all advanced civilisations develop SRPs; just some. That is enough to cause a paradox.
2/ … ‘there aren’t any’ is certainly one of the most popular solutions to the Fermi paradox, and the most likely to be correct. However, we can’t be sure it is the correct answer until we go out there and look.
It is certainly not ‘kooky’.
What is kooky is to make any dogmatic assertion about the probability.
To my knowledge, they’ve said it’s theoretically possible. That’s a far cry from feasible. It’s telling that those you’ve mentioned who’ve spoken favorably about it have no experience building things. Not that I have that experience, but there’s a bizarre assumption they’re making.
Namely, that the machines will be immortal and invulnerable. Is that something that will just inevitably happen? That seems like we’re running up against an actual physics limit.
Oh, is that all?
We’re talking staggering efforts. We would have to devote a large proportion of humanity’s resources to even attempt to accomplish it. Staggering, I tell ya.
The planet Earth will not launch any interstellar missions; the Sol system will eventually launch interstellar missions. This will be after humans and their machines have learned to survive in space indefinitely and colonized everything out to the Kuiper Belt or beyond. So assume a tech base both more advanced AND orders of magnitude larger than ours.
As for the tech to do it, if controlled fusion is possible at all that gives us propulsion adequate for 1-5% speed of light. At the latter figure the stars in our stellar neighborhood about about a100-year journey apart. Freeman Dyson even proposed an interstellar version of his Orion nuclear pulse rocket that would use 1-megaton pulse units. That would require no engineering breakthroughs (although the scale needed is formidable– a one-mile wide pusher plate for example) and would achieve 2-3% speed of light.
A conservative figure for the speed of colonizing the galaxy is about one light-year every 200 years, an average of trip time and building up each newly colonized system until it’s mature enough to spawn its own colonies.
No; any species making technology that is relevant to the fermi paradox. Even non-relativistic SRPs could explore a huge chunk of our galaxy in a “short” time on cosmological scales.
“Even that”?
Again, humans’ entire space escapades cover a few decades. It’s really astonishing the progress we have made in this time. A timescale which is many, many orders of magnitude less that the timescales we’re talking about in the context of the fermi paradox. It would be exactly like claiming that since we haven’t made a quantum computer that can crack RSA encryption, no species ever will. Fusion power station? Must be impossible.
We can’t do it in the near future, so no-one could do it, ever.
Much harder than the apollo program, that’s why it’s a technology of the future, not now. A time where we have greater knowledge, production methods and energy budget.
Yes, assuming continuing progress. Our progress may well halt, but if we’re suggesting that all ETIs’ progress always halts at this point, then is the fermi blocker.
Landing a probe on an asteroid is very obviously progress towards an SRP. This is mental if the argument now is that if you can just assert an arbitrary standard and call that step 1.
Which I have done, and you have not.
That’s not the claim in dispute here. That’s your attempt at strawmanning.
Yes, I have taken the common position that SRPs will likely be possible in millenia, if humans don’t destroy themselves first. But it’s not necessary to the point: say it takes 10,000,000 years. It doesn’t make a different in this context.
No, they accepted the feasibility of the technology, they just thought it was dangerous and argued that the kind of species that would make SRPs would wipe itself out.
I’d be happy to engage with that argument, it would be superior to where we are right now.
How is that a strawman? My point has always been we will never have SRPs.
Ok, I’ll put it to you, if SRPs are inevitable and there has been plenty of time for them to colonize the galaxy, why aren’t we seeing them?
To me the obvious answer is they are not inevitable. Theories like Zoo Hypothesis or Dark Forest are a desperate attempt to cling to SRPs, and are so much pie in the sky.
Here’s an interesting article which suggests that the prokaryote to eucaryote transition, and hence simple life to complex life, began much earlier and in what were from our POV far more hostile surroundings than previously thought.
If this result if accurate this suggests the simple-> complex term of any Drake-like equation is improved. And also suggests an increased probably of more advanced forms of “extremophile” (from our POV) life existing elsewhere.
It also suggests (to me) that the steps from complex unicellular life → multicellular life → macroscopic life took even longer than we thought. Suggesting they are more arduous filters than we thought.
I don’t think we can make any meaningful predictions about any changes in the final value, or even the error bars, of any Drake-like computation. But it’s definitely an interesting result if true.