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this post was submitted on 17 Apr 2024
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Asklemmy
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I'm no nanotech scientist, so I won't pretend I know all of the ins and outs here, but I'm sure when most people think about nanotechnology, they're probably picturing something like the later generation iron man suit from the marvel movies made up of billions of tiny nanobots that can reconfigure themselves and such. If such things will ever be possible, they're still a long way off
I have a hunch you probably have some visions in your head of tiny robots similar in size to a red blood cell swimming around in someone's blood stream, that seemed like a trope that was used by a few different sci Fi series when I was growing up, and certainly the kind of thing I personally picture when I think of nanobots. Problem is, at the nano scale, those kinds of things are kind of huge, a blood cell is a few thousand nanometers across. Most of what we're doing with nanotechnology is just a handful of nanometers in size, at the scale of a few molecules or even atoms. Eventually we may be able to put some of those parts together to make tiny robots and computers and such, but right now we're still kind of figuring out how to make the nuts and bolts and gears and such to make those bots out of.
There's also a lot of nanotech research that you may not really think of as technology but more as something like material science or chemistry. Any time you hear about new developments with carbon nanotubes or graphene, that's nanotechnology. Practical applications for stuff like that are still mostly works in progress, we're probably years, decades, maybe even centuries out before some of those things really come into their own, but when we do work out the bugs, they will absolutely be revolutionary.
But it's not all far future stuff, it's almost guaranteed that you have used and maybe even have in your home or on your person right now something that makes use of nanotech in some way. One example I saw mentioned a lot is sunscreen, there's a lot of sunblock that makes use of zinc oxide and/or titanium dioxide nanoparticles, clothing may contain nanoparticles to help with things like waterproofing, reducing odor, etc. there's lots of mundane nanotech that you're probably already taking advantage of.
As a nano engineer, youre 100% right - with the added slowdowns of safety research. Many of these particles are entirely different beasts on a nanoscale, an example commonly used is microscopic copper is just copper, nanoscopic will have you dead within the hour if inhaled (dont quote my timeframe on that one).
That being said many cool materials are still coming out, just aren't yet at that commercialized availability level yet.
For example graphene has the potential to replace copper -at least in high performance applications- cause its got some fucked levels of conductivity
Edit for some more examples cause I'm a nerd about this stuff:
Carbon nanotubes make vantablack, the material that can absorb 99.9% of visible light (not that exciting beyond a party trick commercially, but in areas trying to minimize electromagnetic noise this is revolutionary).
Silver nanoparticles have been shown to have passive disinfectant properties, leading to the possibility of a cloth that you could run dirty water through and make it drinkable.
And my favorite being we've already created the carbon based structures (can't recall if it was nanotubes specifically) with theoretically high enough tensile strength that if made a couple kilometers long could be used to lasso an asteroid and create a space elavator
About the space elevator thing, even with mystical materials, it'd need to be 110.5km long with a counterweight. Assuming it could work at all on Earth (it can't, but let's assume it can) the amount of material required would be insane. I can't find where anyone has calculated the mass of carbon nanotubes needed, but I'm sure it's out there.
Assuming the material issue is solved somehow though, it's still going through the atmosphere. How does it handle those forces? It's untenable to have on Earth. It's possible on the moon, which would also require much less material since it has less mass.
Thats the coolest part, ie the old thing about a chain only being as strong as its weakest link, and a chain of sufficient length couldn't even hold a feather due to its own weight.
The CNT's (if near perfectly atomically aligned) and give them an INSANE tensile strength, some numbers I just googled puts steel at about 620 MPa (0.62 GPa) whereas the CNT's that have been made are pushing 80 GPa.
Obviously something this big is already gonna be a multi-governmental collaboration, but all you need then is to find the easiest reasonable sized meteor to DART our way, and catch that bitch on the way by.
For the atmosphere part, it would have to be an entirely geostationary orbit, and so really you would have the same winds as expected on skyscrapers (plus a bit). All this the tensile strength has more than enough wiggle room for.
Material costs aren't too bad too considering its nearly a hydrocarbon, and the strength only requires a fairly thin cable - in equivalent terms imagine the material for a road as long, we've got millions of km's of them, 100 is easy
So what about APM? That's the thing I'm waiting for :-)
Shit you and us all.
Worst part of nano is that error is intristic, how much error is where the fun comes in
In the maths in Engines of creation, the errors were supposedly so small they were negligible.
For sure, and thats generally the goal of any engieering - the biggest question is what error are we measuring? Something like vesting a fully autonomous drone, not even close; tubes in a funny shape that trap all light, were already there 99.9%
IIRC it was around one misplaced atom every century for some throughput. It's like digital vs analog or so I understood it.
What's apm?
Atomically Precise Manufacturing.
Where a printer can print an exact copy of itself. For example.
Nanotubes and graphene themselves had a deep hype cycle. They're super strong... as long as they're atomically perfect. The second bit just kind of got left out of the popsci stuff circa-2009.
The biggest thing about technology nobody talks about is manufacturing. The physics was there to design a modern GPU in WWII, it's just that reliably making a thing with few-hundred-atom switches starting with 1940's tools is a very hard problem. The correct approach to do so wasn't even clear until the 70's or so, and then it took many decades of finetuning and building up ever larger and more expensive fabs that can print features that small in environments that perfect.
There's no clear way to place individual atoms of a large object at reasonable price right now. Maybe some kind of biotech will make it possible eventually, or just scaling up current atomic manipulation techniques a lot, but for now CNTs are but high-tech asbestos.