Infinitesimally beared tube mail

In an upgraded street infrastructure some kind of advanced tube mail could be integrated to transport stuff.

Transport of "normal" stuff

Stuff that is not a product of advanced productive nanosystems like:
food, wool, paper, wood, plastic parts, metal parts, glass parts and many more.

Such a design could be imagined as cylindrical capsules (some 10cm in size) in vacuum pipes with capsule propelling shearing drive walls. If the vacuum tube walls are designed as an inflatable structure the system can have very low mass (saving cost). Vibrations may be an issue then though.

Transport of gem-gum stuff

Products of advanced atomically precise productive nanosystems that are sensibly designed can be reversibly disassembled down to their constituting product fragments that are too small to perceive by human senses and sometimes even further down to individual crystolecules that are not permanently "welded" together.

But for transport one actually wants to avoid disassembly below a certain size level. The problem is that with decreasing fragment size the transport friction starts to increase due to the rising surface are that separates moving from resting parts. (TODO: add illustration)

Side-note: The 2D chip like geometry of advanced nanofactories has the same reason. It's a result of minimization of friction. There the transport just happens on a smaller scale. Sub systems separation at the transport layers (moving from stacked sheets to boxes connected with cables) has the same effects as described here and the same motivations to apply or avoid. In fact every transport layer (raw maerial molecules, tooltips, crystolecules) could be coupled to an associated (or a common) capsule transport system. There is no restriction to just the (most useful) microcomponent routing layer which's associated transport system is here on this wiki called "global microcomponent redistribution system".

Eager recycling transport

When products are thrown into a gem-gum waste basket (a nanofactory with upper assembly levels working in reverse) one can tidy up right away and sort microcomponents based on type/ID/tag and bunch them together into bigger single-variety capsules. Those can then be sent through the long range network without too much friction losses.

This is an eager strategy potentially wasteful in time due to execution of unnecessary work potentially reassembling exactly the same structures that have been disassembled.

One reason why one may want to go for this eager strategy is to prevent unpleasant surprises like the need to filter out a highly dispersed microcomponent type that one happens to need in concentrated form in ones new product. The needed microcomponent may be only present highly dispersed in tons and tons of material since this type has rarely/never been used in concentrated form before. Though this is probably a situation that most users likely won't encounter too often.

Lazy recycling transport

Alternatively one can leave quite big chunks and transport them almost unchanged and as is. Further disassembly will only be performed only when really needed at the target location (in the target nanofactory that is making the new recycled product).

This is a lazy strategy potentially wasteful in space due to lacking packing density.

The lazy strategy is remotely akin to deleting data on a hard-drive. The data actually doesn't get overwritten and could potentially be restored. The main difference is that physical base parts can only be permuted (they are immutable) while bits can be deleted or overwritten (to be exact they are thermalized and radiated away).

The optimal size of disassembly will be situation dependent but on average likely rather small.
Maybe an exception with massive as-is or reuse or almost-as-is reuse: "physical object memes". Note that gem-gum products could be highly interactive making them better fit for memes than just say fashion.

Competition with aerial transport?

Full automated aerial transport of goods is already a future that is becoming a reality as of 2026.
See e.g.: https://www.zipline.com/
That does not mean undergraouund transport will become obsolete though.

A few points:

• Underground transport is obviously completely weather independent.
  Goods can be transported just fine in apocalyptic storm conditions. Or even ash rain from a giant volcanic eruption.
• Well beard underground superlube tubes may allow way lower energy losses than with friction from air resistance.
• Traffic via air may be safe but not infinitey safe, which starts to matter for locations where traffic densities get extreme.
• Traffic via air may be silent but not entirely inaudible, which starts to matter for locations where traffic densities get extreme.
• Faster motion does not mean louder, particularly no supersonic booms.
• Fast direct interaction with other underground systems is possible. E.g. with the global microcomponent redistribution system.
• Space colonization related: Off Earth many bodies in the solar system don't eve have atmospheres to begin with.
• More? …

Related

• How small scale friction shapes advanced transport
• Capsule transport
• Global microcomponent redistribution system
• Underground working
• Deep drilling
• Superlube tube