According to the United Nations, about ten percent of the world is undernourished. It's a daunting statistic — unless your name is Hannah Ritchie. She's the data scientist behind the new book Not the End of the World: How We Can Be the First Generation to Build a Sustainable Planet. It's a seriously big thought experiment: How do we feed everyone on Earth sustainably? And because it's just as much an economically pressing question as it is a scientific one, Darian Woods of The Indicator from Planet Money joins us. With Hannah's help, Darian unpacks how to meet the needs of billions of people without destroying the planet.Questions or ideas for a future show? Email us at shortwave@npr.org.