WHY do rich people have all the money? This may sound like the world's silliest question, but it's not. In every society, most of the wealth falls into the hands of a minority. People often write this off as a fact of life--something we can do nothing about--but economists have always struggled to explain why the wealthy take such a big slice of the pie.
If Jean-Philippe Bouchaud and Marc Mézard are right, it is more than a fact of life: it's a law of nature. These two scientists have discovered a link between the physics of materials and the movements of money, a link that explains why wealth is distributed in much the same way in all modern economies. Their theory holds out a scrap of hope to the poor of the world: there may be some surprising ways to make society a bit more equal. And it promises a new fundamental science of money. Economic theory is about to grow up.