User blog comment:GrandMethuselah67/Lore Sheet: The Democratic Imperium of Neohumanity/@comment-4867780-20150810003841/@comment-4867780-20150810062238

I merely meant "extremely" small, since I didn't know the exact ratio. Since femtotech is about performing operations on an extremely small scale, I'm not sure how much it would help in building an astronomically huge structure (scale relation reversed).

I already knew that no space is truly empty, unles the situation is artificially created (which takes an absurd amount of energy). And since the quantity of particules is extremely small, it makes the process radically cost-ineffective, thus unsuited for practical purposes. That's what I meant by "non-viable on a macroscopic scale".