The New York Times recently published an obituary for John Stallings. He passed away on November 24, 2008. John Stallings is probably most well-known for his work on the high-dimensional Poincaré conjecture. He wrote an article about his work on the theorem called “How not to prove the Poincaré conjecture.” (pdf link)
Category: Math
Why do mirrors reverse right and left but not up and down?
Stand in front of a mirror and hold up your right hand. The person standing in the mirror holds up her left hand. Why is that? Why does a mirror reverse left and right? After all, it does not reverse up and down. Before we answer that question, we have to ask a more basic…
How to use KnotPlot
As I’ve mentioned before, I’m teaching a knot theory class this semester. I’ve been playing around with KnotPlot, a powerful piece of software for drawing and working with knots. I want my students use it, but it has a somewhat unintuitive interface. So I’m trying to write up a list of easy-to-use instructions for them. The…
Tetragon fail
This morning I was listening to one of my radio stations on Pandora. One of the automatically-generated songs they played was by tenor saxaphonist Joe Henderson‘s group, the Joe Henderson Quartets. It was from his 1967 album Tetragon. The very mathematical title caught my eye, but so did the accompanying cover art. Obviously the art…
Calculus and sustainability
I saw a number of interesting talks while at the Joint Mathematics Meeting last week. Hopefully I’ll find the time to write about some of them here. One of the presentations that got me the most excited was the minicourse that I attended, Educating about the state of the planet and sustainability while enhancing calculus,…
Publish or perish…?
I just received a copy of The Survival of a Mathematician: From Tenure-Track to Emeritus, by Steven Krantz, to review for MAA Reviews. I am only two pages in and I have already found something interesting (on p. xiv, to be precise). It is a hard fact that most American Ph.D. mathematicians write very few…
Mathematician: top job
I just got back from the Joint Mathematics Meeting in Washington, DC. While I was gone the Wall Street Journal ran an article, Doing the Math to Find the Good Jobs. In it they reveal the best and worst jobs as compiled by Les Krantz, author of “Jobs Rated Almanac.” According to the study, mathematicians…
Happy New Year!
This is one day late, but worth posting despite that, I think. Happy New Year! From Abstruse Goose: Happy Zeno Year
Definition of continuity video
Thank you to Dansmath for turning me on the website xtranormal. It allows you to create your own animated videos. It is easy and fun. You can choose the characters, the scene, the camera angles, the gestures and facial expression, music, etc. They do the voices for you—you just type the script. Here are some of Dan’s videos….
2009 Times Square New Year’s Eve Ball
We can look forward to a very mathematical New Year’s eve ball in Times Square this year. According to the Times Square website: The new Times Square New Year’s Eve Ball is a 12 foot geodesic sphere, double the size of previous Balls, and weighs 11,875 pounds. Covered in 2,668 Waterford Crystals and powered by…
David Richeson: Division by Zero 