Yes, we don't know how to make a half-ton replicating probe right now.
No, none of the arguments on the article have any implication on the possibility of such a probe. None at all.
There's something to look into at the durability argument. The article has no usable information on it, and it's probably not a showstopper. But again, the only thing on the article is that yes, we don't know how to make one such probe right now.
show comments
seiferteric
Wouldn't a counter this argument be biological systems? These are reasonable points as long as we are talking about current methods, but I assume if we were to get to the point of self replicating probes it would be done by something like nanotechnology, synthetic biology like systems.
show comments
zeryx
I studied material science in school specifically to try and address his concerns. Unfortunately they are all quite valid - the hard part isn't manufacturing, extruding, printing. Those are actually all quite reasonable (albeit not super space or weight efficient).
The hard part is refining and ore enrichment, and most techniques that could possibly work in microgravity are almost impossible to test on earth. You would certainly need vitamins for electronics components for a time. Even much older computer chip architectures (1990s level) still require the clean room and 20-30 stages of prep. I believe an orbital chip fab is not only possible but, kind of ideal? Keeping it clean would be within reach - and it's mostly if not entirely an autonomous process from silicon monocrystal to assembled part today.
We're along way from self replicating probes. But I would argue were quite capable of autonomous mining, manufacturing and material transport - assuming we can figure out how to refine effectively. If someone wants a cool PhD project and ship an experiment to the ISS, I would argue an ionic or plasma based refining technique designed for micro gravity could be very interesting and very useful
show comments
PaulHoule
CC asteroids have hydrogen, oxygen and carbon and with chemistry a bit like
I don’t see a problem with drawing flowsheets for metals like iron, stones like silicon and even BTX chemicals to produce plastics. You cycle syngas and treat resulting H2O and CO2 as precious.
Now I was not thinking of a 500kg “seed” but a factory factory that is packed up in 100 ton loads that builds a sunshade factory by a process like building a ship inside a bottle except inside out.
I did worry about how you handle devolatization at the beginning, like it is precious and maybe even dangerous and it would be real nice to do it all at the beginning but you don’t have the storage tank factory online (thought a lot about storage tanks!)
The plan was to do all this in our solar system to sail sunshades to the Earth-Sun L1 point, the big questions I had was “how do you fix problems when it is hands-off that far away?” (physical twin in cislunar space for one thing!) vs “do you send people who you have to keep alive? can you bring them back? do they turn into Zeons?”
I have thought about the Drexler problem when it comes to Mars colonization and can’t think of a better answer than a synthetic biology platform based on bacteria and possibly yeast which can do versatile if not efficient chemical synthesis from syngas or photosynthesis. You still need flow chemistry, 3-d printing and some more methodologies but the project of “advanced manufacturing” that would enable a small settlement to achieve autakry seems achievable to me and would be essential for interplanetary colonization and helpful in case of forced degrowth.
bryanlarsen
If an elderly but distinguished scientist says that something is possible, he is almost certainly right; but if he says that it is impossible, he is very probably wrong.
- Arthur C Clarke
davedx
I did some research on this in the context of self-replicating PV panel construction. I arrived at similar conclusions: mining (ore extraction and refining) was the hardest part. Our current methods involve all involve some kind of high energy system:
- crushing
- breaking down with powerful solutions
- blasting
And a self-replicating probe will (initially at least) be a low energy system. I eventually decided that the pathway with the most likelihood of success would be some kind of very slow crushing/grinding machine that can break down ore into separable components, but then you get into a kind of Darwinist explosive combinatorics research rabbit hole: which crusher/grinder, what kind of machine, how to make something that works on different ore types, what mechanical pressure is better?
Conceptualizing something that can sinter and assemble PV cells was pretty easy, there are broad families of chemistries that work and they mainly differ on input temperatures and output efficiencies. Fairly tractable. But mineral extraction... yeesh, it's extremely difficult.
FWIW on the original article: I think the jump from "insulating wires" to "semiconductor fabs" was kind of obtuse. You don't necessarily need Turing complete PCBs or microchips for most (any?) of this.
M95D
> 2. Is there a credible inorganic-only pathway for electrical insulation and semiconductor packaging?
What about glass, SiO2?
in-silico
One "solution" to these problems is to have the probes land on planets instead of asteroids, and build the necessary infrastructure there.
show comments
voidmain
There is no doubt that compressing a whole industrial supply network into a little probe is incredibly hard.
But I can't see microgravity specifically as a huge challenge. If you can get a probe to another star system, you can probably figure out how to spin it.
show comments
andrewflnr
The thermodynamic argument seems much more important to the Fermi Paradox than any difficulties in refining material, but I don't think I understand it.
show comments
m3kw9
It’s true that current tech can’t do it and he has said it but it doesn’t mean new tech can’t do it. He is assuming other civilizations cannot do it and also assuming probes will be easily detected therefore there are no probes
chopin
Honestly, I always assumed that consensus was that replication is the hardest part. I believe we have almost none of the technologies required for that.
Whenever I read of von Neumann probes I always thought "How can that even made possible?".
credit_guy
> Shrinking that into a 500 kg seed — or even Freitas’ original 100-ton seed — is not an engineering detail. It may be the entire problem.
How many AI tells can you count there?
But honestly (see what I did there?) the AI slop is reasonably cleaned up in this piece.
However, the essence of the argument has two deep flaws. One is that the time to complete an interstellar voyage is extremely long and you need some exergy, yada, yada, yada. We could start with sending self-replicating probes to the asteroid belt. There is zero chance that we'll attempt to send self-replicating probes to a different star system before we send them inside our own solar system. And the second error is this:
> Bootstrapping this loop [...] is a chicken-and-egg problem that no study I am aware of has worked through at the level of actual process flowsheets.
The fact that the current technology is not adequate, and nobody even attempted to solve such a problem is a weak argument. Three hundred years ago nobody had "worked through the process flowsheets" of making an injection molding machine, or a 3D printer, or a power drill, yet they are all available now.
Yes, we don't know how to make a half-ton replicating probe right now.
No, none of the arguments on the article have any implication on the possibility of such a probe. None at all.
There's something to look into at the durability argument. The article has no usable information on it, and it's probably not a showstopper. But again, the only thing on the article is that yes, we don't know how to make one such probe right now.
Wouldn't a counter this argument be biological systems? These are reasonable points as long as we are talking about current methods, but I assume if we were to get to the point of self replicating probes it would be done by something like nanotechnology, synthetic biology like systems.
I studied material science in school specifically to try and address his concerns. Unfortunately they are all quite valid - the hard part isn't manufacturing, extruding, printing. Those are actually all quite reasonable (albeit not super space or weight efficient). The hard part is refining and ore enrichment, and most techniques that could possibly work in microgravity are almost impossible to test on earth. You would certainly need vitamins for electronics components for a time. Even much older computer chip architectures (1990s level) still require the clean room and 20-30 stages of prep. I believe an orbital chip fab is not only possible but, kind of ideal? Keeping it clean would be within reach - and it's mostly if not entirely an autonomous process from silicon monocrystal to assembled part today.
We're along way from self replicating probes. But I would argue were quite capable of autonomous mining, manufacturing and material transport - assuming we can figure out how to refine effectively. If someone wants a cool PhD project and ship an experiment to the ISS, I would argue an ionic or plasma based refining technique designed for micro gravity could be very interesting and very useful
CC asteroids have hydrogen, oxygen and carbon and with chemistry a bit like
https://www.dakotagas.com/
that is, CC asteroid contain “coal” more or less.
I don’t see a problem with drawing flowsheets for metals like iron, stones like silicon and even BTX chemicals to produce plastics. You cycle syngas and treat resulting H2O and CO2 as precious.
Now I was not thinking of a 500kg “seed” but a factory factory that is packed up in 100 ton loads that builds a sunshade factory by a process like building a ship inside a bottle except inside out.
I did worry about how you handle devolatization at the beginning, like it is precious and maybe even dangerous and it would be real nice to do it all at the beginning but you don’t have the storage tank factory online (thought a lot about storage tanks!)
The plan was to do all this in our solar system to sail sunshades to the Earth-Sun L1 point, the big questions I had was “how do you fix problems when it is hands-off that far away?” (physical twin in cislunar space for one thing!) vs “do you send people who you have to keep alive? can you bring them back? do they turn into Zeons?”
I have thought about the Drexler problem when it comes to Mars colonization and can’t think of a better answer than a synthetic biology platform based on bacteria and possibly yeast which can do versatile if not efficient chemical synthesis from syngas or photosynthesis. You still need flow chemistry, 3-d printing and some more methodologies but the project of “advanced manufacturing” that would enable a small settlement to achieve autakry seems achievable to me and would be essential for interplanetary colonization and helpful in case of forced degrowth.
If an elderly but distinguished scientist says that something is possible, he is almost certainly right; but if he says that it is impossible, he is very probably wrong.
- Arthur C Clarke
I did some research on this in the context of self-replicating PV panel construction. I arrived at similar conclusions: mining (ore extraction and refining) was the hardest part. Our current methods involve all involve some kind of high energy system:
- crushing
- breaking down with powerful solutions
- blasting
And a self-replicating probe will (initially at least) be a low energy system. I eventually decided that the pathway with the most likelihood of success would be some kind of very slow crushing/grinding machine that can break down ore into separable components, but then you get into a kind of Darwinist explosive combinatorics research rabbit hole: which crusher/grinder, what kind of machine, how to make something that works on different ore types, what mechanical pressure is better?
Conceptualizing something that can sinter and assemble PV cells was pretty easy, there are broad families of chemistries that work and they mainly differ on input temperatures and output efficiencies. Fairly tractable. But mineral extraction... yeesh, it's extremely difficult.
FWIW on the original article: I think the jump from "insulating wires" to "semiconductor fabs" was kind of obtuse. You don't necessarily need Turing complete PCBs or microchips for most (any?) of this.
> 2. Is there a credible inorganic-only pathway for electrical insulation and semiconductor packaging?
What about glass, SiO2?
One "solution" to these problems is to have the probes land on planets instead of asteroids, and build the necessary infrastructure there.
There is no doubt that compressing a whole industrial supply network into a little probe is incredibly hard.
But I can't see microgravity specifically as a huge challenge. If you can get a probe to another star system, you can probably figure out how to spin it.
The thermodynamic argument seems much more important to the Fermi Paradox than any difficulties in refining material, but I don't think I understand it.
It’s true that current tech can’t do it and he has said it but it doesn’t mean new tech can’t do it. He is assuming other civilizations cannot do it and also assuming probes will be easily detected therefore there are no probes
Honestly, I always assumed that consensus was that replication is the hardest part. I believe we have almost none of the technologies required for that.
Whenever I read of von Neumann probes I always thought "How can that even made possible?".
> Shrinking that into a 500 kg seed — or even Freitas’ original 100-ton seed — is not an engineering detail. It may be the entire problem.
How many AI tells can you count there?
But honestly (see what I did there?) the AI slop is reasonably cleaned up in this piece.
However, the essence of the argument has two deep flaws. One is that the time to complete an interstellar voyage is extremely long and you need some exergy, yada, yada, yada. We could start with sending self-replicating probes to the asteroid belt. There is zero chance that we'll attempt to send self-replicating probes to a different star system before we send them inside our own solar system. And the second error is this:
> Bootstrapping this loop [...] is a chicken-and-egg problem that no study I am aware of has worked through at the level of actual process flowsheets.
The fact that the current technology is not adequate, and nobody even attempted to solve such a problem is a weak argument. Three hundred years ago nobody had "worked through the process flowsheets" of making an injection molding machine, or a 3D printer, or a power drill, yet they are all available now.