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Comment by londons_explore | Hacker News Reader

That's a poor example... The theoretical energy expended to move an object is zero.

All energy losses in moving things are due to inefficiencies that we could theoretically engineer away. For example air resistance could be eliminated with roads becoming vacuum tubes. Wheel friction can be eliminated with magnetic levitation. Braking energy can theoretically be fully recovered, etc.

Today we don't do that because we care about other things (cost etc), but if in the future energy costs went up dramatically, engineers would reconsider...

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> The theoretical energy expended to move an object is zero.

The theoretical energy expended to keep an object moving is zero. The theoretical energy transferred to the object to get it moving is deeply non-zero, even as the energy transferred from the object to get it to stop moving is also nonzero. If you have a finite energy budget, even under theoretical conditions, you can only have a finite number of objects moving up to speed at any given time.

I know you acknowledge this in the rest of your message, but I don't think the original example is poor for the reason you give.

The theoretical energy expended to move an object tends toward zero, without limit, as the allowed time increases. Which is almost the same thing.

(Allowing it to take 12 billion years to move an inch is rather useless, but that's the same issue with the ephemeralization argument in general: it ignores all other measures of "cost".)

There is a hard limit. If you want to get somewhere, you have to get there before the expansion of the universe moves it away forever. Our accessible universe is constantly shrinking. It's a natural law that places firm discontinuities on optimization.

This may seem silly, but microcontroller shrinking is running into a similar problem with quantum noose, which is by far the closer boundary.

The accelerating expantion of the universe also importantly bounds availible time, which makes the specific equation governing how fast optimization can be achieved relevant. For example, if the cost of increasing intelligence is sufficiently exponential past a certain point, a true singularity may never come. And if it's more like busy beaver then exponential then it may be impossible for it to ever get very far indeed.

I really want to call this argument pedantic, but so was mine. And I can't argue against your argument's correctness or validity.

(Well, as far as we know, anyway. Expansion is still the best fitting theory, but there are observable anomalies. Your argument would still win in some other form, perhaps involving Planck Length or similar.)

There are fundamental thermodynamical limits to certain processes involving energy transfer, conversion etc. Heat transfer comes to mind. Those cannot be engineered away.

For simple mechanical systems, yes, inefficiencies can be removed, but it's more like externalizing them. How is the vacuum created and maintained? That requires a compressor, an inherently not lossless machine.

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