Just under the wire…

The February Notices of the AMS features an article on the Four Vertex Theorem. The Four Vertex Theorem states that any simple closed curve in the plane (other than the circle) must have four extrema in its curvature.

Alexander Yong does the honors in this month’s entry in the *What is…* series, What is… a Young tableau. Young tableau arise in many contexts in combinatorics, most dramatically in parametrizing the irreducible representations of the symmetric group.

There are two articles about Mikio Sato, one a summary of his research contributions, and the other an interview. Sato is the inventor hyperfunctions,

We live in a golden age for popular accounts of advanced mathematical research. Robert Griess reviews *Symmetry and the Monster, One of the Greatest Quests of Mathematics*, by Mark Ronan. The book documents the history of the classification of finite simple groups. (In his review, Griess sounds like a skeptic on the question of whether the classification can truly be said to be done.)