American technological creativity is geographically concentrated in areas that are generally distant from the country's most persistent pockets of joblessness. Could a more even spatial distribution of innovation reduce American joblessness? Could Federal policies disperse innovation without...

Historically, urban growth required enough development to grow and transport significant agricultural surpluses or a government effective enough to build an empire. But there has been an explosion of poor mega-cities over the last thirty years. A simple urban model illustrates that in closed...