The Poincaré conjecture has been in the news lately. Russian mathematician Grigori Perelman submitted a proof 3 years ago claiming that he had proved the famous conjecture. In August, he won a prestigious Fields medal for his achievement.

But what is the Poincaré conjecture? Here’s how geometer Jeff Weeks describes it: “Basically, it’s a conjecture about what the simplest possible space is in each dimension.”

“In two dimensions, for surfaces, this has been known for a while [a sphere], but it gets much harder in three dimensions,” he adds.

This description comes from a recent broadcast on the University of Arkansas public radio station KUAF 91.3 FM. Since 2004, mathematician Chaim Goodman-Strauss has been presenting newsy and entertaining math snippets on a program hosted by Kyle Kellams. These weekly segments, called “Math Factor,” are now available as podcasts (http://comp.uark.edu/~strauss/mathfactor/podcast/MathFactor.xml).

In the most recent segment, Goodman-Strauss and Kellams conducted a telephone interview with Weeks, who happened to be in Genoa, Italy. Weeks is the author of *The Shape of Space: How to Visualize Surfaces and Three-Dimensional Manifolds*. He received a MacArthur Fellowship in 1999.

“We’ve discussed cardinality, encryption, paradoxes, puzzles, rates of change, and much more,” Goodman-Strauss says. “For a show about math, it is surprisingly well received by our general audience.”

For a somewhat different sort of edifying experience, you can try an Internet radio station that features all science and math songs, all the time! You can find it at http://www.live365.com/stations/trappedinlab/, but you do need a subscription to the service to hear the music (or you can buy individual tracks). The DJ is Greg Crowther of the University of Washington in Seattle.

This station is associated with the MASSIVE database, which contains information on more than 2,000 science and math songs (available at http://www.science-groove.org/MASSIVE/). “MASSIVE” stands for “Math And Science Song Information, Viewable Everywhere.”

Happy listening!