E = mc² Explained

How would 10 top physicists—two Nobel Prize winners among them—describe Einstein's equation to curious non-physicists? Listen online by selecting Play All or choose individual clips below. Listen offline bydownloading clips, or subscribe to our podcast.

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Nima Arkani-Hamed Theoretical Physicist Harvard University "Things that seem incredibly different can really be manifestations of the same underlying phenomena." Running time 1:23	Janet Conrad Experimental Physicist Columbia University "For me there's a lot more to the equation than E = mc²." Running time 1:32	Sheldon Glashow Theoretical Physicist and Nobel Laureate Boston University "When an object emits light, say, a flashlight, it gets lighter." Running time 2:28

Brian Greene Theoretical Physicist Columbia University "It certainly is not an equation that reveals all its subtlety in the few symbols that it takes to write down." Running time 2:19	Alan Guth Theoretical Physicist MIT "It's easiest to explain by how things looked from the point of view of Newton." Running time 1:46	Tim Halpin-Healy Theoretical Physicist Barnard College, Columbia University "Moving clocks run slow, moving meter sticks are shortened—how does that happen?" Running time 2:13

Lene Hau Experimental Physicist Harvard University "You can get access to parts of nature you have never been able to get access to before." Running time 1:09	Michio Kaku Theoretical Physicist City University of New York "E = mc² is the secret of the stars." Running time 1:05	Neil deGrasse Tyson Astrophysicist American Museum of Natural History "It's something that doesn't happen in your kitchen or in everyday life." Running time 2:48

Frank Wilczek Theoretical Physicist and Nobel Laureate MIT "Ninety-five percent of the mass of matter as we know it comes from energy." Running time 1:01