Common critique towards diamondoid atomically precise manufacturing and technology

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All these common critiques have been analyzed and identified as non-showstoppers some even helping rather than hurting.

This page coveres common critique directed towards macroscale style machinery at the nanoscale and gemstone based atomically precise manufacturing and technology. These critique points are common due to …

  • expert knowledge of scaling laws that is incomplete in important areas
  • current day experimental restrictions

Guide for responding to critique:
This page can be seen as a guide for how to best respond to such critique.
Fight scaling laws with scaling laws.

Page organization:
The common critique points are mainly organized by how they relates to scaling laws and to each other. Some further critique is related to mechanochemistry.

For a more general & free-form discussion see page:
Common misconceptions about atomically precise manufacturing
There may be some redundant overlap in discussion.

Scaling law (SL) based critiques

Rising surface area per volume (SL)

– rising friction power losses (TRUE BUT)
See: Why larger bearing area of smaller machinery is not a problem
– nanomachinery motions couple strongly to thermal motions (FALSE)
Due to practical reasons simulations are usually done at extremely high speeds >100m/s. That is way above the actual proposed machine operation speeds of ~5mm/s or lower. Also see: Stroboscopic illusion in animations of diamondoid molecular machine elements. This can be quite misleading in judgement of friction levels.

– rising corrosion rate (oxidation/rust) (FALSE)
Systems are well sealed and expose only corrosion resistant surfaces to the outside. Internals are PPV.
– perfect vacuum can't be created but is needed (FALSE)
No PPV is not physically impossible. It is just unattainable with today's (2023) technology and macroscopic volumes.

– lubricants and dirt clog machinery like molasses and gravel (FALSE)
Sealed systems again. Bearings run dry and are either slide-bearings or roller gear bearings. Related: Atomically precise bearings

Rising effect of viscosity (SL)

– lubricants and dirt clog machinery like molasses and gravel (FALSE)
Dirt is already covered above. Systems operate dry. No liquids or gasses involved. Well except in resource supply. There several strategies can be employed including:

  • fractal supply channels
  • last stretch diffusion transport
  • compartmentalized transport of liquids (Capsule transport)

Rising influence of thermal motion (SL)

Nanomachinery motions couple strongly to thermal motions (FALSE)
Already covered above.

★ placement of atoms is to unreliable (error rates) jittery and sloppy/wobbly fingers (FALSE)

In context of general possibility:
Sufficient lattice scaled stiffness to suppress constrain thermal motion amplitudes is attainable even at room temperature. Error rates drop further exponentially with cooling. Theoretical exploratory engineering analysis in the tooltip cycle paper. Experimental corroboration in a huge number of papers on subatomically precise imaging and atom manipulation.
In context or of possibility across the bootstrapping pathway.
– The direct path goes straight to systems that have sufficient lattice scaled stiffness. The remaining (always finite) error rates can be dealt with several strategies and can be made FAPP sufficiently low. Some strategies easier for early primitive systems some harder. Strategies like out of place mechanosynthesis, error detection (failed synthesis step / failed entire crystolecule), failed part disposal, and perhaps (but not necessarily) failed synthesis step error correction. That is possibly more challenging than the incremental path but not provenly so.
– The incremental path proposes to go incrementally to stiffer more advanced materials or combine materials of different stiffness and different scalability. (Scalability in the sense of termination control not size). While fat fingers still apply initially for soft systems this restriction gradually diminishes with increasingly stiff materials. Machine phase can be attained gradually via topological atomic precision, tether-aided selfassembly, site-activation-wash-in approaches, and Combining advantages of different selfassembly technologies.
See also: Jittery fingers, Wobbly fingers, Sloppy fingers

★ atoms do not stay in place due to surface diffusion or surface reconstruction (FALSE)
In strongly bonding covalent materials (including diamond) surface diffusion rates at room temperature are so astronomically low that FAPP atoms do not hop at room temperature. Even taking the large numbers of atoms in macroscopic objects into account. During mechanosynthesis the actively worked on patch of surface can be sufficiently stable too. So determined in the tooltip cycle paper (exploratory engineering). Cooling helps. For early primitive mechanosynthesis experiments are needed to identify and take on more immediate challenges.
(wiki-TODO: Add: Diamond depassivated surface reconstruction analysis paper)

★ nanosystems can only work in an dynamic equilibrium (FALSE)
This assumes unavoidability of high thermally induced bond braking rates and a need to deal with them.
As discussed above (finite) thermally induced bond braking rated are FAPP zero for the far term target materials of interest.
Early systems along the incremental path face the challenge of dynamic equilibrion, yes, but they do not disprove the existence of systems that are exempt.
(wiki-TODO: maybe explain further)

  • rising influence on quantum mechanics
  • rising tendency towards themodynamic equilibrium

Rising influence of quantum mechanics (SL)

Machinery quantum disperses, quantum collapses, and tunnels (FALSE)
Runs apart omnidirecttionally, reappears elsewhere spontaneously, moves through itself and walls.
See: Nanomechanics is barely mechanical quantummechanics

Rising tendency towards thermodynamic equilibrium (SL)

Perfect vacuum can't be created but is needed (FALSE)
Already covered above.

– diffusion transport is (fundamentally) more efficient (FALSE)
In fact the opposite may be true due to the trick of dissipation sharing not being usable in diffusion transport.
– nature would have done it if it where possible (FALSE)
See: Nature does it differently

– atoms do not stay in place due to natural ambient high energy radiation (TRUE BUT)
It is true that that some radiation can not be shielded against. Especially with smaller systems/devices not even giving enough space for shielding against hard UV. But expectable radiation damage seems to be low enough to be dealable with though via redundant system design (fail-safe redundancy) alone. Disassemblying component testing and reassembing or even having difficult self repairing systems are a bonus. This has been analyzed in Nanosystems and reviews would be appreciated.

– nanosystems can only work in an dynamic equilibrium (FALSE)
Covered above.
– nature would have done it if it where possible (FALSE)
Covered above.

Falling material stiffness (SL)

– placement of atoms is to unreliable (error rates) jittery and sloppy fingers (FALSE)
Covered above. Also see: Same relative deflections across scales for the aspect of deflections from mechanical accelerations.
Deflections from machine motions (rather than thermal agitation) are FAPP zero at proposed speeds of ~5mm/s.

Falling available space (SL) – obviously

– Not enough space for all the manipulators (TRUE BUT)
See: Fat fingers and Atom placement frequency

Rising influence of intermolecular forces (SL)

– atoms adhere to manipulators "sticky fingers" (TRUE & GOOD THING)
See: Sticky finger problem

Mechanochemistry related critiques

potential problems with machine phase chemistry including mechanosynthesis
All of the following already covered above.

  • placement of atoms is to unreliable (error rates) jittery and sloppy fingers (FALSE)
  • perfect vacuum can't be created but is needed (FALSE)
  • atoms adhere to manipulators "sticky fingers" (TRUE & GOOD THING)
  • Not enough space for all the manipulators (TRUE BUT)

Potential problems not based on any scaling laws

– too difficult, castel in the sky, chicken egg problem (FALSE)
– advocating stiff nanomachinery but forking with soft nanomachinery to get to stiff nanomachinery ASAP is hypocrism (FALSE)
– it's better to just wait and see (FALSE) & the worst possible decision

Related

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