Robots may one day rule the world, but what is a robot-ruled Earth like?
Many think the first truly smart robots will be brain emulations or "ems." Scan a human brain, then run a model with the same connections on a fast computer, and you have a robot brain, but recognizably human.
Train an em to do some job and copy it a million times: an army of workers is at your disposal. When they can be made cheaply, within perhaps a century, ems will displace humans in most jobs. In this new economic era, the world economy may double in size every few weeks.
Some say we can't know...