THE aim of this book is to provide a course of pure mathematics that will be useful to students of economics. The earlier chapters, which deal with numbers and variables and their representation, with ...

In the Fall I'll be starting teaching again, after a semester away on sabbatical and then enjoying teaching relief during my first semester at Penn. I'll be teaching a course that I truly love, and ...

When Hannah Cairo was 17 years old, she disproved the Mizohata-Takeuchi conjecture, a long-standing guess in the field of harmonic analysis about how waves behave on curved surfaces. The conjecture ...