In principle yes. The simplest is the idea of a "clanking replicator". I.e. a big clumsy looking machine - could even be multi-story or spread over acres of the surface of the planet or Moon to ensure that there is everything there it needs to be able to create a copy of itself.
We can almost do that already, with a few gaps to be filled. Perhaps if we had a big trillion dollar type push that we had to achieve it somehow, we could do it already.
We have 3D printers that can print nearly all of their parts. Indeed there is a project dedicated to making self replicating printers
RepRap - RepRapWiki
Not totally self replicating - it can't print its own computer chips. But we do also have nanoscale printers on their way.
Here is one that can print down to 25 nanometers scale. Well sub visible resolution (200 nm is the resolution limit of the best optical microscopes)
Northeastern reveals NanoOPS 3D printer that prints nanoscale electronics
This is an earlier 2013 real time video from another company called Nanoscribe GmbH tshowing nanoscale printing of a miniature spaceship model on micron scale
More videos here:
A 3D Printed Spaceship On The Scale Of A Human Hair? Hello Nanoscribe 3D Printer
And here is a fractal nanotruss
So, this could already be used to print electronics. After all, the electronics you make don't have to be particularly fast or efficient for a self replicator, just needs to be able to do the job. If necessary just make everything larger and slower.
For a self replicator - say on the Moon - or maybe you send materials from the Moon to LEO where self replicating solar panels use the material to generate more solar panels.
Well you need it to be able to first mine the raw materials. This could be a major challenge though given the wide variety of materials used in most machines. So before that, to simplify the task, probably you will try to design your self replicator to use as few different materials as possible.
Then to convert that to components it can use to build copies of itself, assemble those, and also make its own chips.
Hard to say how soon this will all come together but I think it could be possible within a few decades, not that far into the future.
Right now we are nowhere near being able to do it though in practice. A lot of things to be sorted out.
The other possibility is to have small self replicators, cell sized, microbe sized self replicators. So, we already have those of course with living cells. The thing is- could we do that artificially? Imitate the capabilities of a living cell in some artificial way?
So - that's more challenging. And also has more safety issues than the "clanking replicator".
In both cases it seems wise to have an "off switch".
So - you could limit it to, say, 10 generations - like an artificial telemore - some counter that goes down with each generation and on the tenth generation then it stops - the tenth generation is no longer able to replicate and you have to start again with a new first generation if you need more.
That then reduces the chance of unexpected effects due to mistakes in replication. Plus add lots of checks to make sure that it is an exact copy and if it isn't just destroy it, re-use its materials to make another machine.
And I think as well build in an overall override, an off switch, some signal you can create easily and easily detected, which would instantly stop all the self replicating machines anywhere from replicating. If again limited to 10 generations then that reduces also the chance of it replicating with a malfunctioning "off switch" but you'd need to take a lot of care over that also to make sure it can't happen and the off switch works.
Or the other way around - some signal - or some material - that it has to be supplied with at regular intervals to keep going - that's safer really. E.g. it needs to receive some encrypted signal which it can't generate itself say once a day - or else it just automatically switches itself off and goes into dormancy until it receives that signal again.
If we have both of those, and so long as nobody is stupid enough to disable and remove these overrides, I think we could be able to use self replicators responsibly.
We can almost do that already, with a few gaps to be filled. Perhaps if we had a big trillion dollar type push that we had to achieve it somehow, we could do it already.
We have 3D printers that can print nearly all of their parts. Indeed there is a project dedicated to making self replicating printers
RepRap - RepRapWiki
Not totally self replicating - it can't print its own computer chips. But we do also have nanoscale printers on their way.
Here is one that can print down to 25 nanometers scale. Well sub visible resolution (200 nm is the resolution limit of the best optical microscopes)
This is an earlier 2013 real time video from another company called Nanoscribe GmbH tshowing nanoscale printing of a miniature spaceship model on micron scale
More videos here:
A 3D Printed Spaceship On The Scale Of A Human Hair? Hello Nanoscribe 3D Printer
And here is a fractal nanotruss
Fractal nanotruss. Individual components are as small as 5 nanometers. (Image: L. Meza, L. Montemayor, N. Clarke, J. Greer/Caltech) from Nanotechnology and 3D-printing
So, this could already be used to print electronics. After all, the electronics you make don't have to be particularly fast or efficient for a self replicator, just needs to be able to do the job. If necessary just make everything larger and slower.
For a self replicator - say on the Moon - or maybe you send materials from the Moon to LEO where self replicating solar panels use the material to generate more solar panels.
Well you need it to be able to first mine the raw materials. This could be a major challenge though given the wide variety of materials used in most machines. So before that, to simplify the task, probably you will try to design your self replicator to use as few different materials as possible.
Then to convert that to components it can use to build copies of itself, assemble those, and also make its own chips.
Hard to say how soon this will all come together but I think it could be possible within a few decades, not that far into the future.
Right now we are nowhere near being able to do it though in practice. A lot of things to be sorted out.
The other possibility is to have small self replicators, cell sized, microbe sized self replicators. So, we already have those of course with living cells. The thing is- could we do that artificially? Imitate the capabilities of a living cell in some artificial way?
So - that's more challenging. And also has more safety issues than the "clanking replicator".
In both cases it seems wise to have an "off switch".
So - you could limit it to, say, 10 generations - like an artificial telemore - some counter that goes down with each generation and on the tenth generation then it stops - the tenth generation is no longer able to replicate and you have to start again with a new first generation if you need more.
That then reduces the chance of unexpected effects due to mistakes in replication. Plus add lots of checks to make sure that it is an exact copy and if it isn't just destroy it, re-use its materials to make another machine.
And I think as well build in an overall override, an off switch, some signal you can create easily and easily detected, which would instantly stop all the self replicating machines anywhere from replicating. If again limited to 10 generations then that reduces also the chance of it replicating with a malfunctioning "off switch" but you'd need to take a lot of care over that also to make sure it can't happen and the off switch works.
Or the other way around - some signal - or some material - that it has to be supplied with at regular intervals to keep going - that's safer really. E.g. it needs to receive some encrypted signal which it can't generate itself say once a day - or else it just automatically switches itself off and goes into dormancy until it receives that signal again.
If we have both of those, and so long as nobody is stupid enough to disable and remove these overrides, I think we could be able to use self replicators responsibly.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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