Mathematicians just made a big leap forward on one of the field’s all-time favorite problems. Curves—squiggly lines through space, such as a comet’s trajectory or a stock market trend—are some of math ...

There are two kinds of leaders: One type is what I call the "rational optimist," who can see opportunities in difficult situations and respond appropriately when problems arise. I consider the other ...

Making good decisions is not easy, and making the best possible (“optimal”) decisions is even harder. Instead, humans often use shortcuts and rules of thumb. From firm managers and policymakers to ...