Robert Gordon: The death of innovation, the end of growth FROM Ted Talk

"There are four headwinds that are just hitting the American economy in the face. They're demographics, education, debt and inequality. They're powerful enough to cut growth in half. So we need a lot of innovation to offset this decline. And here's my theme: Because of the headwinds, if innovation continues to be as powerful as it has been in the last 150 years, growth is cut in half. If innovation is less powerful, invents less great, wonderful things, then growth is going to be even lower than half of history."