Economist Robin Hanson’s new book “The Age of Em: Work, Love and Life when Robots Rule the Earth” imagines a not-too-distant future when robots are commonplace in our life. And the smartest of these will be “ems,” or brain emulations.  These will be super-detailed scans of actual human brains that run as models on computers. And once we figure out how to pull that off cheaply, ems will take over most human jobs. 
The advantage ems will have is that they’ll be running 1,000 times faster than an actual human brain. You’ll also be able to copy them. Wouldn’t you rather scan and duplicate the brain of a Stephen Hawking and have that em do almost everything?  
The moment when ems will take over is similar to the singularity famously proposed by the futurist Ray Kurzweil. But Hanson thinks a brain em will come in the next 100 years, sooner than …