For years, pundits have warned that the world's soaring population ... will usher in an age of scarcity. We already have a hard time supplying 7 billion people with food, with energy, with water. What happens when we hit 9 billion, the Earth's projected population in 2050? Stefan Heck and Matt Rogers say the resources are there - and the way we use them is about to undergo radical change. In their new book, Resource Revolution, they argue that information technology and advanced materials science, combined with new business models, will enable companies and societies to do far more with far less. It will be, they claim, a jump in productivity and efficiency greater than anything seen before. Heck, who teaches resource economics at Stanford University, and Rogers, a director of the McKinsey & Co. consulting firm, spoke with The Chronicle. Q: So current forecasts call for the world to add 2 billion people by 2050. Do we have the resources to give them a decent standard of living? Rogers: Take an example California faces right now - water. If you look at the next 20 years, we need to double the economic output for every unit of water we use. The good news is, in agriculture, we have a set of technologies where we can get much higher yields with the water that's available. Q: How about energy? Rogers: This resource revolution affects both how we produce and consume energy. With the dramatic increases in fuel economy we're seeing, from electrification and hybrids but also improvements in the internal combustion energy, you see an ability to improve the use of energy.