[b0rsuk]

That kind of growth requires constant inventions, rather than occasional inventions to use in existing factories. Also I think efficiency improvements offer diminishing returns (sorry I can't prove it). But there's only so much value you can get from a handful of matter, especially if it has to be cost-effective. At some point you bump into limits of physical properties.

A silly tale I read in an old popular science book: Aliens arrive at the Earth. They make peaceful contact with humans and want to exchange knowledge. They get every single human book ever printed, they drop them on a pile, then... one of them takes a metal rod out of his pocket, and makes a scratch on it somewhere in the middle. THERE, it's archived. All they need is to measure the exact spot where the scratch is made and calculate the ratio of rod below the scratch to the rod above the scratch. The decimal representation of that irrational number encodes entire human knowledge.