Prof Proves Problem
Steven Hofmann became curious when a professor introduced him to the problem when Hofmann was an undergraduate. In 1996, the problem took over Hofmann's life until he solved it in 2000. It's called Kato's Conjecture, and applies to the theory of waves moving through different media, such as seismic waves traveling through rock. Hofmann solved the problem in a 120-page paper he wrote with several colleagues. The International Congress of Mathematicians has invited him to speak in Madrid, Spain next year.