1890s, while working on her doctoral thesis in Paris, Marie Curie proposed for the first time that radiation was not some kind of chemical reaction between molecules, but something intrinsic to the atom—a discovery so critical to the development of physics, in fact, that she would become the first woman ever to win a Nobel Prize. Her research quickly drew the attention of her husband, Pierre Curie, who abandoned his own research into crystals to focus on radiation. Together they discovered that radioactive elements decayed at constant rates. The half-life of carbon 14, for instance, is 5,730
...more