Common misconceptions about atomically precise manufacturing

APM is a very novel area of research and development that dives into fields of knowledge that are yet pretty alien for most people including many "nanotechnology" experts. When encountering a new network of knowledge one usually tries to apply existing knowledge to judge statements and claims - what else can one do. Without deeper understanding of the relationships this can lead people into trapdoors. Some are so bad that almost everyone falls in. This page is guide around those trapdoors.

It's called "nanotechnology" - not anymore

Note that the term "nanotechnology" is as specific as the term "makrotechnology" that's seldom used because it is so unspecific. Nanotechnology is a huge field and a big part of research is done on interesting things that are on the verge of falling apart - rather the opposite of atomically precise manufacturing (APM) where the most stable structures are the ones of interest.

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Some concepts are not exactly wrong but simply unproportionally over-represented in current mainstream media partly because they carry the "nano" tag. See: The usual suspects

We must learn from nature thus advanced productive APM must look similar to molecular biology - wrong

It's like saying: "We must learn from nature thus planes must look like birds." There undoubtedly are things to learn (especially on the deeper not the superficial levels) but there are lots of things to shun. So much that one ends up at systems that are very different from natural ones. Technology already has shown countless of times that it can go where evolution couldn't. Probably the most obvious difference is that in fairly advanced artificial system it is better to shun brownian motion for the most part rather than to use it in exactly the way like nature does.

Since molecular biology uses diffusion transport to do work factory style transport does not work at the nanoscale - wrong

There simply was/is no continuous path of small incremental steps towards this kind of technology that molecular biology could have followed. It takes humans to do this. See: Diffusion transport

Makro scale style machinery is not suitable for nano scale devices at all - wrong

Simply wrong. - See: [1]
For an other explanation see further below.

Nanobots - in most cases a very flawed image

Associated traits that have nothing to do with advanced productive APM systems:

• swarms
• living & evolving
• insatiable, metabolize just about anything
• super dangerous - the accident is unavoidable and cataclysmic

APM is like swarms of "nanobots" - wrong

The main body of AP systems and products will be bulk materials produced by nanofactories. Loose autonomous units for productive purposes or only for applicative purposes (where loose means unconnected & floating in air or water or "crawling" on surfaces applicable e.g. in form of sprays) are unpractical in relation to nanofactories.

All kinds of loose units out of diamond like materials may pose environmental problems since spill of non-dissolving non-rotting material into the biosphere can have detrimental effects on many organisms for a long period of time.

Loose units should thus be used only in limited ways by non rouge actors where there are no other options. One such case are medical purposes. They are somewhat of an exception. Their bio-compatible products don't resemble the productive units themselves thus they can be made devoid of any self replication capability.

Pretty advanced APM systems (way beyond basic advanced APM systems) make swarms of loose productive units undeniable possible but they are over- and most often misrepresented in current media. SciFi is regularly painting unrealistic pictures of the classic dystopia.

Those "nanobots" can "eat" just about anything - wrong

Main article: atomically precise disassembly

It is often thought that the capability of taking things apart atom by atom would become available just when one starts to be able to put things together atom by atom. This is far from true. Taking things apart atom by atom is a much harder problem in many cases. Beside other factors the inability to consume just about anything harshly limits the aforementioned grey goo scenario.

No disassembly.

Related

• evolution

Almost everything will be buildable - often misunderstood

It is often thought that APM is supposed to be able to produce almost anything (often formulated: all allowed structures permissible by physical law) including e.g. food, wood, plastics and metal parts but this is surely not the case.

The range of materials and structures targeted actually lies in a very narrow range (see: "mechanosynthesis"-page).
The magic lies in the diamondoid metamaterials that emulate properties above the atomic level.

This is not to say it will be impossible for all times to assemble materials (or rather compounds) lying outside the narrow set of now targeted materials. When the technology will have been around for quite a while very advanced extensions may be able to do this but this is way beyond the scope of any current day APM attainment project because it is beyond the horizon of useful exploratory engineering.

No food from gem-gum factories

Future gem-gum factories are not in any way intended to be usable for food production. Structures out of solvated weakly linked non stiff proteins and lipid layers are a good example of "anti-diamondoid" materials. Specialized devices will be capable of some limited form of synthesis of food.

Attempting to create genetic twin tissue (avoiding the need for a complete scan) has the problem that information extraction from DNA to a spacial (not only typological) atom and molecule configuration is not straightforward to say the least. There's not only the forward protein folding problem but also the yet unsolved riddle how body shape at all scales is encoded.

Why an perfect 1:1 copy of a steak is and will stay impossible

Attempting to create exact copies down to atomic resolution of an original tissue at this point seems ridiculously complex. Some kind of very advanced scan (atomically precise disassembly) of the original would be needed to be performed in advance. Trying to compress quasi-random atom configurations data hierarchically like in diamondoid APM systems would probably lead to strange unnatural compression artifacts. The need to produce everything in a frozen state (ice crystals) might be a hard problem but one of the most minute ones.

Tasty "meta-food" may be creatable (given sufficient design effort in chain molecule mechanosynthesis capabilities)

Creating something edible by mixing pure synthesizes molecules together (quite a lot of sloppy molecules need to be synthesizable thus not something to expect early on) together would produce something like an advanced nourishment dough. One may be able to fake familiar food for the human senses or make something else heterogeneous and tasty but it's questionable whether we really desire to fool ourselves. At some ends deficiencies through lopsided nutrition may arise while at other ends food might get a lot healthier. A mixed nutrition with natural food will probably be best.

Competing with cheap potatoes is hard

Note: Plants are already self replicating and thus cheap. Most people just don't grow all of the plants they consume because they need space, sun, soil, and often industrial post processing. Advanced (technical) APM will bring all the other stuff to the same or lower price level per mass. Including means for easier plant breeding.

To be competitive with the cheap self replicating food that we eat today tissue construction via advanced mechanosynthetic means (e.g. a pie like this hoax [2]) must be quite a bit faster than biological machinery. This may be expectable but at this point the highly diverse tool-tip chemistry at cryogenic temperatures and at the threshold of stability needed poses a prohibitively high barrier. That is barely any exploratory engineering can be applied here. Further some kind of hierarchical assembly that completely replaces the natural system would be needed.

Other sources of synthetic food

Also other technology branches (bio-nanotechnology ...) unrelated to APM may be able to produce edible tissues before of after we attain advanced APM capabilities.

Flawed critics about the fundamentals

Macro-scale style machinery isn't suitable for the quantum world one needs something more exotic instead - wrong

Via a very simple estimation it turns out that nanomechanics is actually barely mechanical quantum-mechanics. Baffling? The fact that quantum-mechanics is called quantum-mechanics is just a somewhat unlucky result of science history. Basically mechanics was generalized to the point where it also encompasses the behavior of electrons thus to the point where it encompasses what is in eveready language considered electronics. And electronics are pretty quantum mechanical at the nanoscale. Of course certain nanomechanic systems can be made quantum mechanical in behavior if the conditions are made extreme enough.

Actually under conditions expectable in advanced atomically precise production devices nanomechanics is pretty classical in behavior. Since the objective is to transport stuff from A to B in a controlled manner just like in makrotechnology using makro-style-machinery (with some minor tweaks) makes perfectly sense and has even advantages such as superlubrication and dissipation sharing.

Thermodynamics prevents one from having every atom at the place we want it - wrong for practical scales

If one just looks at the atom displacements from thermal movement at room temperature alone big macroscopic slabs of stiff diamondoid materials stay atomically precise for long periods of time from a human perspective. More serious are effects from hard ionizing radiation that can't be shielded effective against with. Reliability and redundancy make things work practically nevertheless. Self repair can extend lifespans to uncalculable ranges.

• Zyvex about error rates

There are many materials that do not keep their atoms at a constant place due to thermal motion. They do not preserve their bond topology. Many metals behave that way especially on their surface. Even water does not keep its atoms at its fixed at its molecules. It swaps around hydrogen atoms due to its molecular auto-ionization pH7 H₃O⁺ OH^-.

But there are also many materials (among them e.g. diamond) with bonds strong enough such that the constituent atoms for all practical purposes do not leave their lattice places due to thermal motion (radiation is a different story). Even when there are macroscopic amounts of material sitting around for decades at room temperature.

Biological systems (e.g. Proteins, DNA, RNA, ...) feature strong bonds. But almost all the involved molecules are chain molecules. And (oversimplifying a bit) with chains only one link needs to break for the whole chain to break. Biological systems also tend to be embedded in a potentially aggressive chemical environments (aggressive relative to a vacuum). Thus although biological systems feature strong bonds they need (and have) some active repair mechanisms to keep everything roughly where it is.

Having crystolecules with a dense mesh of redundant polycyclic bonds in a vacuum makes the time it takes for them to incur destructive damage long enough for them to be extensively used even without any repair. Self repair in advanced nanosystems (in the sense of part replacement) is an available but not unconditionally necessary option.

Related:

• science vs engineering
• low error rate of digital systems
• Neo-polymorphs - exclusively mechanosynthetically accessible highly stable stable non equilibrium polymorphs of compounds
• Wikipedia: Thermodynamic equilibrium

Advanced APM systems are a "castle in the sky" with no way to built them - not quite

It has often be perceived that diamondoid molecular elements can only be synthesized by stiff tools made that themselves are made from diamondoid molecular elements. The incremental path avoids circular dependencies by continuously changing the method of assembly from self assembly to stereotactic control. (Radical Abundance - page 190)

The direct path tries to use bigger already stiff but not quite atomically precise slabs of material to build stiff atomically precise structures (e.g. in MEMS-AFMs). This is not fundamentally impossible but a much steeper slope judging from the progress rates.

Atoms can't be placed individually because of "fat and sticky fingers" - sticky is actually good fat is just untrue for the tips

Disproved by basic experimental and detailed theoretical work. See: Mechanosynthesis. It may get a bit more challenging when the mechanosynthesis of complex chain molecules is attempted. Which is not a requirement for gem-gum-factories.

One can't make soft materials from diamond - wrong

See: "emulated elasticity" for why this is not true.

Minor ones

Diamond has a much lower density than silicon - wrong

Quite the opposite actually - diamond is pretty heavy for its volume:

• Diamond: 3.5–3.53 g/cm³
• "(Diamond+Silicon)/2" ~= Moissanite: 3.218–3.22 g/cm³ (heavier than the average density)
• Silicon: 2.3290 g/cm³
• Quartz: 2.65 g/cm³ (denser than silicon although there are voids and lighter oxygen interspersed - how??)