IMA Public Lecture: Mathematics Making Sense of Sensors ~ Robert Ghrist, University of Pennsylvania, January 22, 2009 Fibonacci-Inspired British National Wildflower Center Free Mathematics Books ~ 254 (legal) e-books Price Drop: Stocks, Homes, Now Triple-Word Scores ~ This article contains a beautiful infographic containing the frequency of letters in the English language compared to Scrabble…

# Month: March 2009

## Great conference on a rainy Saturday

I brought my knot theory students to our regional meeting of the MAA today (the EPaDel section). It was one of the best EPaDel meetings I’ve attended. There were parallel talks, so it was hard to decide who to see. I decided to watch the student talks in the morning and the invited talks in…

## Ambigrams

John Langdon is a typographer who has become famous for his ambigrams. An ambigrams is a word or words that has some sort of symmetry, frequently a rotational or mirror symmetry. Langdon’s work became well known after it appeared in Dan Brown’s best-selling novels The Da Vinci Code and Angels & Demons. Apparently Brown named…

## Mythematics: a call for participation

I thought I would try a little experiement here. Recently some high profile mathematicians have been using a blog to conduct a massively collaborative mathematics project. What a brilliant idea that could be done today, with our current technology! I have nothing so grand in mind, but I thought I’d try something in the same…

## Photo in Focus

Cool! I received the February/March 2009 issue of MAA Focus. I always enjoy this issue because I get to pick out people I know from among the snapshots taken at the Joint Mathematics Meeting. Each year I know more of them. It is fun. This year I was happy to see a photo of one…

## Recommended readings (3/22/09)

The Four Color Problem Gets a Sharp New Hue ~ the strong perfect graph conjecture is settled: a graph with neither an odd hole nor an odd anti-hole is perfect Surfaces the Ooze of the Past ~ it was nice to find this post after writing my post on surfaces last week How to Build Your…

## Bubbles with knotted boundaries

We can think of a mathematical knot as a knotted piece of string (or in our case, wire) with its free ends joined. Examples are shown below. There is a remarkable theorem that every knot can be realized as the boundary of a surface. Moreover, Herbert Seifert produced a very simple algorithm for constructing an orientable…

## Congress designates 3/14 National Pi Day

In the news: Ya can’t make it up: House praises pi National Pi Day? Congress makes it official Here’s the vote on C-Span. The vote was 391 yeas, 10 nays, 30 not voting. Who were the 10 Representatives who voted against it? Jason Chaffetz (R-Utah) Jeff Flake (R-Arizona) Dean Heller (R-Montana) Timothy Johnson (R-Illinois) Jeff…

## The area versus the circumference of a circle

I just found this stop motion animation that I made last year when I was playing around with the iStopMotion software. So I uploaded it to YouTube and posted it here for you all to see. It is not the highest quality, but it was fun to make. It shows the Greek method of relating…

## Putting mathematical scholarship in perspective

At our college tenure decisions (as well as other personnel and salary decisions) are made by an all-college committee with faculty members from a variety of departments. There must be at least one faculty member from the sciences, but there may be no mathematician on the committee. Thus it is extremely important for the chair…

## Recommended readings (3/12/09)

An ancient typo ~ Has no one noticed this before?!? Stackable letters ~ A new way to classify letters of the alphabet Mathematician answers Supreme Court plea ~ A fair division problem for voting Wolfram|Alpha is coming! ~ The next Segway or the next Google? An Appel a day ~ Seven colors suffice for a…

## Flashlights and conic sections

Recently, Ξ over at the 360 blog wrote about hyperbolic light (which was inspired by the article, “The Shape of Lamp Shade Shadows” by Kenneth E. Horst, The Physics Teacher, Volume 39, March 2001). They were looking at the pattern of light on the wall emitted by a desk lamp with a cylindrical lampshade. They observed that the…