By the end of the 23rd century, human (or rather transhuman) mastery of the physical world reached its summit. Although the civilization was still limited by energy needs and basic laws of physics, things in the macro world could be reshaped and created freely. This was achieved by mastering the nanotechnology. First Nanomachines were pretty stupid, and their use was limited to spraying clouds of highly specialised nanobots to perform simple tasks, thus efficiently producing (or growing) things as desired - but only in a controlled environment. Even the military nanobots weren't that smart, but their task - to destroy - was pretty easy. Not so with the Nanites. As the miniaturization progressed, those compact machines grew much more complex and powerful. With the rise of Hyperturing AIs, even nanomachines could posess some dose of intelligence, but what's more important there were now intelligences powerful enough to efficiently control untold masses of Nanites, so they could adapt and perform just any task desired.