Difference between revisions of "Molecular assembler (disambiguation)"

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[[File:Replicating-molecular-assemblers_screencap_BBC-Horizon_Nano-utopia_1995_480p_high-contrast.jpg|400px|thumb|right|Depicted: The (dated) concept of replicating diamondoid molecular assemblers. Here two ''free floating'' assemblers are in the process of copying themselves. Screencap from BBC Horizon doku "Nanoutopia" (1995)]]
 
[[File:Replicating-molecular-assemblers_screencap_BBC-Horizon_Nano-utopia_1995_480p_high-contrast.jpg|400px|thumb|right|Depicted: The (dated) concept of replicating diamondoid molecular assemblers. Here two ''free floating'' assemblers are in the process of copying themselves. Screencap from BBC Horizon doku "Nanoutopia" (1995)]]
 
[[File:self-replicating-assembler-unit.png|thumb|Artistic depiction of a mobile assembler unit capable of self replication (linked to a "crystal" of assemblers and thus not ''free floating''). An outdated idea.]]
 
[[File:self-replicating-assembler-unit.png|thumb|Artistic depiction of a mobile assembler unit capable of self replication (linked to a "crystal" of assemblers and thus not ''free floating''). An outdated idea.]]
'''Note: The concept of advanced molecular assemblers for [[diamondoid|diamondoid materials]] is outdated!'''<br>
 
The current concept for advanced productive nanosystems of the "[[in-vacuum gem-gum technology]]" type are [[Nanofactory|atomically precise small scale factories]].
 
  
The three main problems with molecular assemblers are that they are:
+
The basic idea is a machine which packages all the functionality to produce useful products and also make copies of itself (directly with [[diamondoid]] [[mechanosynthesis]]). This way one gets an exponential rate of replication and one can produce macroscopic goods in reasonable amounts of time.
 +
 
 +
= Two contexts – bootstrapping and advanced systems =
 +
 
 +
'''Molecular assemblers usually considere in one of two contexts.'''
 +
* As means for [[bootstrapping]] towards [[diamondoid]] gemstone based advanced productive nanosystems.
 +
* As an actual diamondoid gemstone based [[advanced productive nanosystem]]s.
 +
'''For a clear analysis it's important to not mix these two contexts.''' <br>
 +
For details on these two contexts …
 +
* see page (1): [[Proto-assembler (outdated)]] and
 +
* see page (2): [[Molecular assemblers as advanced productive nanosystem (outdated)]] respectively
 +
 
 +
'''Note: The concept of advanced molecular assemblers for [[diamondoid|diamondoid materials]] is outdated.'''<br>
 +
The current concept for [[advanced productive nanosystem]]s of the "[[in-vacuum gem-gum technology]]" type are [[Nanofactory|atomically precise small scale factories]].
 +
 
 +
== The 3 problems of molecular assemblers ==
 +
 
 +
'''Three main problems with molecular assemblers are that they are:'''
 
* inefficient
 
* inefficient
 
* hard to reach
 
* hard to reach
 
* undesirable
 
* undesirable
But molecular assemblers are:
+
* (but not fundamentally impossible)
* not fundamentally impossible
+
Depending on the chosen context these matter to various degree. <br>
 +
Visit the pages, linked (1) and (2) above, for their respective discussion.
  
Molecular assemblers are member of the class of [[mobile naoscale robotic devices]] ("nanobots").<br>
+
== Problematic ultra-comact self-replication in both contexts ==
Molecular assemblers may emerge as products of advanced nanofactories (among other more useful "nanobots").
+
  
= The idea =
+
In the case of [[proto-assembler]]s these machines need to be very compact due to the harsh limitations in [[scanning probe microscopy]]. <br>
 +
Typically suggested are one to a few hundred nanometers in side-lengths.
  
The idea is/was to create a machine with side-lengths of a few hundred nanometers which packages all the functionality to produce useful products and also make copies of itself (directly with [[diamondoid]] [[mechanosynthesis]]). This way you get an exponential rate of replication and can produce macroscopic goods in reasonable amounts of time.
+
I the case of of [[molecular assemblers as advanced productive nanosystem (outdated)]]
 +
such limitations from [[scanning probe microscopy]] are absent though <br>
 +
a typical assumption is one active site for [[mechanosynthesis]] per assembler
 +
(and no convergent assembly) also posing harsh limits on assembler size for reasonable levels of throughput.
  
== Reasons for the problems ==
+
Overall molecular assemblers are highly compressed ultra compact replicators by definition. <br>
 +
Giving a very restricted and difficult design space.
  
'''inefficiency:'''<br>
+
= Molecular assemblers in the technical book [[Nanosystems]] =
It turned out that packaging all the functionality into such a small package is a rather unbalanced and inefficient approach for [[in-vacuum gem-gum technology]]. This can be seen in the [[Nanofactory layers|nanofactory cross section image]] where it is visible that the bottommost assembly levels (there arranged as stacked coplanar layers) take the largest portion of the stack. In the small package of an assembler the bottommost layers would be highly underrepresented making it rather slow (and inefficient).
+
  
'''difficulty to reach:''' <br>
+
'''There aren't any. They are not mentioned.'''<br>
See page: "[[Direct path]]".
+
The closest thing to molecular assemblers in Nanosystems is Section 16.3.6. Minimal diamondoid-material systems and<br>
 +
it starts with: '''>>Any attempt to describe a "minimal" system must be considered speculative.<<'''
  
'''reason for undesirability:''' <br>
+
There is no proposal to build a diamondoid proto-system with a scanning probe tool (of macro- or microscale). <br>
The [[grey goo horror fable]] toned waay down to realistic levels.<br>
+
Scanning probe tools are only mentioned (subsection f. Summary.) as tools for analysis: <br>
Still far down the road in the future (state 2017 .. 2022) and heavily limited by the requirements of the [[reproduction hexagon]].
+
''>>Molecilar probes can be used to determine the outcome of operations within a single device, ...<<''
 +
 
 +
If anything this is rather meant as a later stage in the technical development ladder <br>
 +
that one likely will finds better/other solutions for (e.g. a less compact system). <br>
 +
 
 +
Also there is no mention about mobility and free-floating non-mountedness. <br>
 +
A trait that is often ascribed to molecular assemblers and <br>
 +
a trait necessary for the [[grey goo]] scenario to sound plausible.
  
 
== Assembler hype hiding progress to nanofactoies ==
 
== Assembler hype hiding progress to nanofactoies ==
  
The assembler concept was a natural and obvious [[bioanalogy]] to introduce initially. <br>
+
The assembler concept was a natural and obvious [[Misleading biological analogies that should be avoided|bioanalogy]] to introduce initially. <br>
Continued refinement with [[exploratory engineering]] quickly led away from it though but this went almost unnoticed.
+
Continued refinement with [[exploratory engineering]] quickly led away from it though but this went almost unnoticed. <br>
 +
Initially no clear distinction was made between systems for bootstrapping and far term target systems as thee not yet was any deeper analysis.
  
The combination of their appearance (legs or other mechanisms to move about) with their very tightly packed capability of [[self replication]] in their vacuum "belly" that seem akin to a "whomb" led to the situation that the public started to perceive this technology as swarms of tiny life like nano-bugs that could potentially start uncontrollable and unstoppable self replication.
+
The combination of their appearance (legs or other mechanisms to move about) with their very tightly packed capability of [[self replication]] in their vacuum "belly" that seem akin to a "whomb" was one factor in leading to the situation that the public started to perceive this technology as swarms of tiny life like nano-bugs that could potentially start uncontrollable and unstoppable self replication.
  
 
Why this is a rather miss-informed perception can be read up [[Common misconceptions about atomically precise manufacturing#Nanobots - in most cases a very flawed image|here]] and [[the grey goo meme|here]].
 
Why this is a rather miss-informed perception can be read up [[Common misconceptions about atomically precise manufacturing#Nanobots - in most cases a very flawed image|here]] and [[the grey goo meme|here]].
Line 50: Line 78:
 
* the design of [[robotic mechanosyntesis core]]s
 
* the design of [[robotic mechanosyntesis core]]s
  
=== Old assembler designs ===
+
= Possible exceptions =
  
Quite a bit of thought was put into the assembler model [Todo: link KSRM]. Either they where supposed to swim about in a solution or there was some form of movement mechanism in a machine phase scaffold crystal envisioned like:
+
'''Occasions where somewhat molecular assembler like designs may not yet be completely outdated.'''
 
+
* sliding cubes [TODO add references]
+
* legged blocks [TODO add references]
+
 
+
= The ribosome and similar artificial biomimetic nano"machines" =
+
 
+
These are also often called ''molecular assembler'' although they are:
+
* non self replication
+
* critically dependent on brownian movement
+
* and can only assembles floppy linear chain molecules which again need brownian motion to fold into something useful
+
 
+
= Block placing assembler linkage =
+
 
+
Unlike diamondoid assemblers this idea is not outdated.
+
Atomically precise building blocks from structural DNA nanotechnology that are pre-produced by self assembly
+
could be assembled to passive block manipulator linkages by those same passive block manipulator linkages after a first one was put together manually.
+
Actuation could be from a chips surface (see [[technology level I]]) and self replication could work in the form of [[exponential assembly]].
+
 
+
* [[Crystolecule assembly robotics]] might become capable of more or less compact self replication with predelivered "vitamin" pasts from the [[mechanosynthesis core]]s.
+
* Wikipedia: [https://en.wikipedia.org/wiki/Clanking_replicator Clanking replicator]. A term to distinguish macroscale selfreplication from nanoscale selfreplication. But [[crystolecule]] level self replication is very similar to macroscale self replication. So the meaning can be dragged back. A '''clanking nano replicator''' so to say. (Sidenote: actual clanking "sounds" should be avoided. Sound emission = loss of energy = inefficient operation = need for waste heat removal)
+
 
+
= Possible exceptions where somewhat molecular assemblers like designs may not yet be completely outdated =
+
  
 
The only place where the slow and inefficient molecular assembler concept may be practically usable is for <br>
 
The only place where the slow and inefficient molecular assembler concept may be practically usable is for <br>
Line 82: Line 88:
  
 
But even there a multi part system is more practical and likely. <br>
 
But even there a multi part system is more practical and likely. <br>
So it wold not operate alone but rather in conjunction with [[microcomponent maintenance unit]]s.
+
So it would not operate alone but rather in conjunction with [[microcomponent maintenance unit]]s.
  
= Microcomponent mainenance units ≠ Molecular assemblers =
+
= Importance of delineation =
 +
 
 +
Molecular assemblers are member of the class of [[mobile nanoscale robotic device]]s ("nanobots") <br>
 +
or even more generally [[Mobile robotic device]].<br>
 +
'''For a clear analysis it's important to be aware of these other nanobot (and microbot) concepts and not mix them up with molecular assemblers.''' <br>
 +
Some concrete examples further down. <br>
 +
Also see: [[Mobile robotic device]] <br>
 +
<small>If mixing is intentionally better give the new concept a new name.</small>
 +
 
 +
= Delineations =
 +
 
 +
'''Easy to confuse but different to molecular assemblers are:'''
 +
* [[Utility fog]]
 +
* [[Gemstone based medical nanobots]]
 +
* [[Microcomponent maintenance unit]]
 +
 
 +
'''Other things that too are sometimes called molecular assemblers:'''
 +
* Block placing assembler linkage
 +
* The ribosome and similar artificial biomimetic nano"machines"
 +
 
 +
== Microcomponent mainenance units ≠ Molecular assemblers ==
  
 
Main page: [[Microcomponent maintenance unit]]
 
Main page: [[Microcomponent maintenance unit]]
Line 94: Line 120:
 
But a [[microcomponent recomposer device]] is a macroscopic device whereas a [[microcomponent maintenance unit]] is a microscopic one.
 
But a [[microcomponent recomposer device]] is a macroscopic device whereas a [[microcomponent maintenance unit]] is a microscopic one.
  
= Molecular assemblers in the technical book [[Nanosystems]] =
+
== Block placing assembler linkage ==
  
'''There aren't any. They are not mentioned.'''<br>
+
Unlike "diamondoid molecular assemblers" this idea is not outdated. <br>
The closest thing to molecular assemblers in Nanosystems is Section 16.3.6. Minimal diamondoid-material systems and<br>
+
Atomically precise building blocks from structural DNA nanotechnology that are pre-produced by self assembly
it starts with: ''>>Any attempt to describe a "minimal" system must be considered speculative.<<''
+
could be assembled to passive block manipulator linkages by those same passive block manipulator linkages after a first one was put together manually. <br>
 +
Actuation could be from a chips surface (see [[technology level I]]) and self replication could work in the form of [[exponential assembly]].
  
There is no proposal to build a diamondoid proto-system with a scanning probe tool (of macro- or microscale). <br>
+
* [[Crystolecule assembly robotics]] might become capable of more or less compact self replication with predelivered "vitamin" pasts from the [[mechanosynthesis core]]s.
Scanning probe tools are only mentioned (subsection f. Summary.) as tools for analysis: <br>
+
* Wikipedia: [https://en.wikipedia.org/wiki/Clanking_replicator Clanking replicator]. A term to distinguish macroscale selfreplication from nanoscale selfreplication. But [[crystolecule]] level self replication is very similar to macroscale self replication. So the meaning can be dragged back. A '''clanking nano replicator''' so to say. <br>(Sidenote: Actual clanking "sounds" should be avoided. Sound emission = loss of energy = inefficient operation = need for waste heat removal)
''>>Molecilar probes can be used to determine the outcome of operations within a single device, ...<<''
+
  
If anything this is rather meant as a later stage in the technical development ladder <br>
+
== The ribosome and similar artificial biomimetic nano"machines" ==
that one likely will finds better/other solutions for (e.g. a less compact system). <br>
+
  
Also there is no mention about mobility and free-floating non-mountedness. <br>
+
These are also often called ''molecular assembler'' although they:
A trait that is often ascribed to molecular assemblers and <br>
+
* are not capable of independent self replication
a trait necessary for the [[grey goo]] scenario to sound plausible.
+
* are critically dependent on brownian motion / diffusion transport
 +
* can only assembles floppy linear chain molecules which again need brownian motion to fold into something useful
  
 
= Related =
 
= Related =
 
+
* '''[[Proto-assembler (outdated)]]'''
 +
* '''[[Molecular assemblers as advanced productive nanosystem (outdated)]]'''
 +
----
 +
'''The three problems of molecular assemblers that make them an outdated concept:'''
 +
* [[Why ultra-compact molecular assemblers are too inefficient]]
 +
* [[Why ultra-compact molecular assemblers are too difficult]]
 +
* [[Why ultra-compact molecular assemblers are not desirable]]
 +
----
 +
* [[Why nanofactories are not molecular assemblers tacked to a surface]]
 +
----
 
* [[No nanobots]]
 
* [[No nanobots]]
 
* [[Mobile robotic device]]
 
* [[Mobile robotic device]]
Line 119: Line 154:
 
* The better alternative that is now instead targeted: [[Gemstone metamaterial on chip factories]]
 
* The better alternative that is now instead targeted: [[Gemstone metamaterial on chip factories]]
 
* Still quite compact but less compact self replication by adding one additional assembly level: [[Second assembly level self replication]] <br> This would likely be a system of more or less mobile components on a surface or chip.
 
* Still quite compact but less compact self replication by adding one additional assembly level: [[Second assembly level self replication]] <br> This would likely be a system of more or less mobile components on a surface or chip.
 
 
{{wikitodo|add image of dividing cells illustrating the analogy - use it on other related pages too - goo}}
 
{{wikitodo|add image of dividing cells illustrating the analogy - use it on other related pages too - goo}}
 +
----
 +
* [[gemstone metamaterial on-chip factory]] – Identified as promising far term target via [[exploratory engineering]]
 +
----
 +
* [[Whole nanofactory selfreplication]]
  
 
= External links =
 
= External links =

Latest revision as of 18:33, 4 May 2024

Depicted: The (dated) concept of replicating diamondoid molecular assemblers. Here two free floating assemblers are in the process of copying themselves. Screencap from BBC Horizon doku "Nanoutopia" (1995)
Artistic depiction of a mobile assembler unit capable of self replication (linked to a "crystal" of assemblers and thus not free floating). An outdated idea.

The basic idea is a machine which packages all the functionality to produce useful products and also make copies of itself (directly with diamondoid mechanosynthesis). This way one gets an exponential rate of replication and one can produce macroscopic goods in reasonable amounts of time.

Two contexts – bootstrapping and advanced systems

Molecular assemblers usually considere in one of two contexts.

For a clear analysis it's important to not mix these two contexts.
For details on these two contexts …

Note: The concept of advanced molecular assemblers for diamondoid materials is outdated.
The current concept for advanced productive nanosystems of the "in-vacuum gem-gum technology" type are atomically precise small scale factories.

The 3 problems of molecular assemblers

Three main problems with molecular assemblers are that they are:

  • inefficient
  • hard to reach
  • undesirable
  • (but not fundamentally impossible)

Depending on the chosen context these matter to various degree.
Visit the pages, linked (1) and (2) above, for their respective discussion.

Problematic ultra-comact self-replication in both contexts

In the case of proto-assemblers these machines need to be very compact due to the harsh limitations in scanning probe microscopy.
Typically suggested are one to a few hundred nanometers in side-lengths.

I the case of of molecular assemblers as advanced productive nanosystem (outdated) such limitations from scanning probe microscopy are absent though
a typical assumption is one active site for mechanosynthesis per assembler (and no convergent assembly) also posing harsh limits on assembler size for reasonable levels of throughput.

Overall molecular assemblers are highly compressed ultra compact replicators by definition.
Giving a very restricted and difficult design space.

Molecular assemblers in the technical book Nanosystems

There aren't any. They are not mentioned.
The closest thing to molecular assemblers in Nanosystems is Section 16.3.6. Minimal diamondoid-material systems and
it starts with: >>Any attempt to describe a "minimal" system must be considered speculative.<<

There is no proposal to build a diamondoid proto-system with a scanning probe tool (of macro- or microscale).
Scanning probe tools are only mentioned (subsection f. Summary.) as tools for analysis:
>>Molecilar probes can be used to determine the outcome of operations within a single device, ...<<

If anything this is rather meant as a later stage in the technical development ladder
that one likely will finds better/other solutions for (e.g. a less compact system).

Also there is no mention about mobility and free-floating non-mountedness.
A trait that is often ascribed to molecular assemblers and
a trait necessary for the grey goo scenario to sound plausible.

Assembler hype hiding progress to nanofactoies

The assembler concept was a natural and obvious bioanalogy to introduce initially.
Continued refinement with exploratory engineering quickly led away from it though but this went almost unnoticed.
Initially no clear distinction was made between systems for bootstrapping and far term target systems as thee not yet was any deeper analysis.

The combination of their appearance (legs or other mechanisms to move about) with their very tightly packed capability of self replication in their vacuum "belly" that seem akin to a "whomb" was one factor in leading to the situation that the public started to perceive this technology as swarms of tiny life like nano-bugs that could potentially start uncontrollable and unstoppable self replication.

Why this is a rather miss-informed perception can be read up here and here.

  • Dystopian SiFi fantasy anchored the idea of assemblers in the public perception (at least in USA and UK).
  • Nanofactories coming close to the newer detailed concepts remain yet to be seen in fiction.

Partial design aspects of molecular assemblers that remain applicable

Many considerations about assemblers are still relevant:

  • methods for movement e.g. for the transport of microcomponents and self repair by microcomponent replacement in the higher assembly levels of nanofactories. The legged block mobility design is also known from the concept of (speculative) utility fog but has other design priorities in a manufacturing context like more rigidity and less "intelligence".
  • methods for gas tight sealing and locking parts out
  • and many more ...
  • the design of robotic mechanosyntesis cores

Possible exceptions

Occasions where somewhat molecular assembler like designs may not yet be completely outdated.

The only place where the slow and inefficient molecular assembler concept may be practically usable is for
self repair situations where the demand on product throughput rate is exceptionally low.
Like fixing low rates of damage from natural background radiation.
See: Self repairing system#In place self-repair

But even there a multi part system is more practical and likely.
So it would not operate alone but rather in conjunction with microcomponent maintenance units.

Importance of delineation

Molecular assemblers are member of the class of mobile nanoscale robotic devices ("nanobots")
or even more generally Mobile robotic device.
For a clear analysis it's important to be aware of these other nanobot (and microbot) concepts and not mix them up with molecular assemblers.
Some concrete examples further down.
Also see: Mobile robotic device
If mixing is intentionally better give the new concept a new name.

Delineations

Easy to confuse but different to molecular assemblers are:

Other things that too are sometimes called molecular assemblers:

  • Block placing assembler linkage
  • The ribosome and similar artificial biomimetic nano"machines"

Microcomponent mainenance units ≠ Molecular assemblers

Main page: Microcomponent maintenance unit

Molecular assemblers are not to confuse with microcomponent maintenance units.
These are also relatively small and compact but they are incapable of mechanosynthesis.
More abstractly they have no manufacturing or demontage capabililities on the lowest assembly level.
Just like a microcomponent recomposer device.
But a microcomponent recomposer device is a macroscopic device whereas a microcomponent maintenance unit is a microscopic one.

Block placing assembler linkage

Unlike "diamondoid molecular assemblers" this idea is not outdated.
Atomically precise building blocks from structural DNA nanotechnology that are pre-produced by self assembly could be assembled to passive block manipulator linkages by those same passive block manipulator linkages after a first one was put together manually.
Actuation could be from a chips surface (see technology level I) and self replication could work in the form of exponential assembly.

  • Crystolecule assembly robotics might become capable of more or less compact self replication with predelivered "vitamin" pasts from the mechanosynthesis cores.
  • Wikipedia: Clanking replicator. A term to distinguish macroscale selfreplication from nanoscale selfreplication. But crystolecule level self replication is very similar to macroscale self replication. So the meaning can be dragged back. A clanking nano replicator so to say.
    (Sidenote: Actual clanking "sounds" should be avoided. Sound emission = loss of energy = inefficient operation = need for waste heat removal)

The ribosome and similar artificial biomimetic nano"machines"

These are also often called molecular assembler although they:

  • are not capable of independent self replication
  • are critically dependent on brownian motion / diffusion transport
  • can only assembles floppy linear chain molecules which again need brownian motion to fold into something useful

Related


The three problems of molecular assemblers that make them an outdated concept:



(wiki-TODO: add image of dividing cells illustrating the analogy - use it on other related pages too - goo)



External links