Revision as of 18:15, 26 August 2023

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

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.

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

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 fingers (FALSE)
See: Jittery fingers, Sloppy fingers

– atoms do not stay in place due to surface diffusion or surface reconstruction (FALSE)
– nanosystems can only work in an dynamic equilibrium (FALSE)
(wiki-TODO: explain)

• 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 diffusion transport. – nature would have done it if it where possible (FALSE)
(wiki-TODO: add link)

– atoms do not stay in place due to natural ambient high energy radiation (TRUE BUT)
(wiki-TODO: explain things with fail-safe redundancy & self repair)

– 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

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

• Macroscale style machinery at the nanoscale
• Common misconceptions about atomically precise manufacturing (older less systematic page)