This might be the most erudite chemistry post ever on Less Wrong. @Eric Drexler actually comments here on occasion; I wonder what he would have to say.
I have been trying to sum up my own thoughts without getting too deeply into it. I think I would emphasize first that the capabilities of plain old DNA-based bacteria are already pretty amazing—bacteria already live everywhere from the clouds to our bloodstreams—and if one is worried about what malevolent intent can accomplish on the nanoscale, they already provide reason to be worried. And I think @bhauth (author of this post) would agree with that.
Now, regarding the feasibility of an alternative kind of nanobot, with a hard solid exterior, a vacuum interior, and mechanical components… All the physical challenges are real enough, but I’m very wary of supposing that they can’t be surmounted. For example, synthesis of diamondoid parts might sound impossibly laborious; then one reads about “direct conversion of CO2 to multi-layer graphene”, and thinks, could you have a little nano “sandwich maker” that fills with CO2 (purified by filter), has just the right shape and charge distribution on its inner surfaces to be a substrate for the formation of graphene, and which clamps shut when a particular current flows, opening afterwards to reveal a customized nanosheet that can become a tube or a layer or a surface…
You’re right that cells do all this stuff already, but stochastically, with self-assembled floppy parts in an aqueous environment, and so on. You could view the decades of discussion about mechanical nanotechnology, as a long theoretical study of whether and how rigid mechanical paradigms can also be introduced on the nanoscale. What I would say is that, if one is specifically interested in nanobots made of “diamondoid”, one can also investigate the extent to which the biological paradigm can be imported into that world, to create hybrid designs which opportunistically use whichever approach works.
I almost replied with the same point, but thought, “Nah, bacteria do sometimes end up in blood.” Bacteremia is an unnatural condition for humans. Either the immune system clears it, or it progresses to sepsis and you die.
This might be the most erudite chemistry post ever on Less Wrong. @Eric Drexler actually comments here on occasion; I wonder what he would have to say.
I have been trying to sum up my own thoughts without getting too deeply into it. I think I would emphasize first that the capabilities of plain old DNA-based bacteria are already pretty amazing—bacteria already live everywhere from the clouds to our bloodstreams—and if one is worried about what malevolent intent can accomplish on the nanoscale, they already provide reason to be worried. And I think @bhauth (author of this post) would agree with that.
Now, regarding the feasibility of an alternative kind of nanobot, with a hard solid exterior, a vacuum interior, and mechanical components… All the physical challenges are real enough, but I’m very wary of supposing that they can’t be surmounted. For example, synthesis of diamondoid parts might sound impossibly laborious; then one reads about “direct conversion of CO2 to multi-layer graphene”, and thinks, could you have a little nano “sandwich maker” that fills with CO2 (purified by filter), has just the right shape and charge distribution on its inner surfaces to be a substrate for the formation of graphene, and which clamps shut when a particular current flows, opening afterwards to reveal a customized nanosheet that can become a tube or a layer or a surface…
You’re right that cells do all this stuff already, but stochastically, with self-assembled floppy parts in an aqueous environment, and so on. You could view the decades of discussion about mechanical nanotechnology, as a long theoretical study of whether and how rigid mechanical paradigms can also be introduced on the nanoscale. What I would say is that, if one is specifically interested in nanobots made of “diamondoid”, one can also investigate the extent to which the biological paradigm can be imported into that world, to create hybrid designs which opportunistically use whichever approach works.
>to our bloodstreams
Nitpick: https://www.nature.com/articles/s41564-023-01350-w
”No evidence for a common blood microbiome based on a population study of 9,770 healthy humans”
Of course, skin, digestive tract, reproductive tract, etc. all have lots of bacteria.
I almost replied with the same point, but thought, “Nah, bacteria do sometimes end up in blood.” Bacteremia is an unnatural condition for humans. Either the immune system clears it, or it progresses to sepsis and you die.