What Happened to Nanotech?

"Nanotech" was a click bait buzzword before "click bait" was a word. We have it, and its fulfilling many promises, in the form of integrated circuits. We had those but larger when the promises of "nanotech" were being sung.

We have "nanopore" filters and they're doing fun things in chemistry and medicine.

As for mechanisms, we have things like accelerometers and microphones and DLP image chips ... useful but complicated mechanisms have maintenance requirements and that becomes a problem when all we can do at that scale is "fire and hope" manufacture. Try to make lots of a thing, hope some of the things come out properly, dont worry about the ones that dont.

i dont think we'll have "nanobots" for a long, long time. Cultured microorganisms will be easier, we're not going to beat proteins by building tiny metal brakes and welders: metals aren't the same at that scale.

Drexler had two ideas for how molecular manufacturing would work: (i) something like a robot arm that would pick and place atoms, and (ii) a mill with molecular gears, conveyor belts and stuff like that.

Circa 1990 some researchers at IBM pushed some atoms around on a surface to spell "IBM" and visualized it with a scanning probe microscope, which seems like a baby step towards (i). To accomplish (i) you need a tip that can pick up an atom and push it to a reaction site and make the reaction happen, much like an enzyme. If you had the tip you could put it on a probe and start building, but we don't. (I do wonder though how you sense the environment to know that the last reaction went right, where the source atom is, etc.)

So far as (ii) I think to biological systems for inspiration and it's something chemists are making gradual progress on

https://www.nature.com/articles/s41467-020-17814-0

Only if Nokia Mobile had survived, we could have seen something in this space. Here is what Nokia Research Labs(in Cambridge, UK) and Cambridge Univesity were working on before Nokia exited the mobile space:

https://www.youtube.com/watch?v=ymbFfoiHbOg

https://www.youtube.com/watch?v=Aw2yiOhsFsc

At least Drexler-style nanotech, there was someone in like the organic chem or biochem world 15 years ago or so who observed that Drexler’s vision was very billiard-ball when the real thing is more sticky and probabilistic.

Arguably mRNA vaccines are specialised nanobots.

Also, depending on what scale you allow, the armies of microcontrollers now suffused into all sorts of machines are such things.

As might be the software bots for good and ill infecting some of our machines.

More generally, marketing folk and 'thought leaders' fling all sorts of (often unhinged) verbiage at the walls without asking engineers what is plausible, so no one should be astonished or disappointed when most doesn't stick.

Nano tech was dependent on nuclear fusion reactors to power their sentient AI which runs on quantum computing core. So I expect we are only 10 years away from widespread mass production.