Digital control over reversibly composable units of matter
This does not mean digital control over manufacturing machinery.
This does mean digital control over matter.
Contents
Discrete pieces & scale independence
One very advanced form of digital control over matter is to have the capability
to control the placement of individual atoms FAPP fully deterministically.
But digital control over matter is also possible at the macroscale.
Prerequisite for that is that there are pre-made standard building blocks that are reversibly recomposable.
These can be pre-produced via various manufacturing methods including 3D-printing, casting, injection molding or whatever is feasible.
Note that while the machines for the preproduction can and likely will be under digital control this is not digital control over matter.
What is digital contol over matter is the subsequent reversible pick and place assembly and recomposition of these pre-built parts.
Bits are structurally reversible (not necessarily energetically reversible). They can be discretely written and deleted.
Digital control over matter thus needs to have its pieces discretely addable and removable.
Actually due to the facts that …
- physical pieces cannot be magically deleted (or spawned) "POOF" and
- removal implies reversibe connection mechanisms
… digital control over matter implies an analogy not just to digital logic
but to reversible logic.
(Side-note1: Reversible logic features the potential for energetic reversibility.)
(Side-note2: Note that immutability is compatible with reversibility as there are is uncomutation in retractile cascades.)
See related page: Tracing trajectories of component in machine phase
Error prevention
Self centering structures can help funneling parts to the places where they are supposed to go.
Macroscopically without heavy vibrations there is a super exponential drop in error rate.
At some point the error rate is literally zero
At the nanoscale what represents the funneling in piezomechanosyntehsis are the attractive spots on the crystal lattice.
Relevant here for the error rates is the quantity of lattice scaled stiffness.
Conceputually one can think of it like this:
A system fully in machine phase has zero entropy. Everything is known.
A placement mechanism has some placement error that "intends" to introduce some entropy into the system.
The self centering funnel or crystal lattice point attraction restores the entropy to zero.
Entropy can only grow. So where does the entropy go you ask? Sound and heat of course.
Energetically this is not relevant at macroscale the annoying clanking sound is though (clanking replicator).
At the nanoscale the energetic loss will eventually become relevant though and subject to optimization (see idea: Dissipation sharing).
What one essentially does is pumping out the entropy to the impulse space before any of it can seep into position space.
Optiization form minimization of loss of energy (dissipation)
Stiffer robotic structures and slower operation speeds give lower ingress of entropy per assembly step.
This lowers dissipation and allows (but does not necessitate) for smaller funneling structures or materials with lower lattice scales stiffness.
Error correction
Error rates in piezomechanosynthesis or bigger scale pick-and-place processes can be kept low by repeatedly testing results.
This can be as simple as by touch, not necessarily a need for cameras that wouldn't work at the nanoscale.
Repeated testing for correct assembly scales exponentially essentially allowing FAPP perfectly error free nanocomponents like crystolecules and microcomponents.
pressing down the error rate that is already low to begin with die to other means.
Of course there is radiation damage at bigger scales.
This can be taken by whole system redundancy and more advanced things like self repair
(also strongly based on the digital control of matter foundation).
Related
- Shannon information theory
- Error correction
- Common misconceptions – "Thermodynamics prevents one from having every atom at the place we want it" - wrong for practical scales
- ?? parity bits and more complicated redundancy schemes ??
- Digital manufacturing – usually just referring to digital control of machines that have analog control over matter
