The Ladies Chained

Viewpoints Conference Math and Folk Dance Presentation

About two weeks ago I gave a talk titled Patterns and Mathematics in Traditional Folk Dances at the Viewpoints Grand Reunion Conference. The presentation is the final result of a combination of a workshop on math and contradancing that I taught with my colleague Amy Cann, lots of late night conversations and thinking while preparing to teach that class and some communication with a mailing list full of dance callers. In the presentation I spent most of my time talking about contradancing, though there are some stuff in the end about maypole dances, sword dances and waltzes. Since I promised at least several people a copy of my slides I’ve decided to just put them up here.

Slides for Math and Traditional Dance talk at Viewpoints 2008 (12MB PDF file)

There are several important caveats regarding these slides.

1. The file is a 12 MB PDF file because of a good number of pictures and diagrams.
2. There are spelling mistakes and typos. I can’t fix them because the original Keynote file is 100 miles away on another computer.
3. This is the 60+ slide version along with many slides that I did not actually present. So it should be more understandable without my endless ranting. The last bits are, however, still quite incomprehensible with the slides alone.
4. The bibliography is not actually done yet. I’ll post it here once I have it done.

Currently I’m trying to turn the presentation into a paper. If you have any suggestions or ideas or whatever, send me a note!

Cowboys and Morris Dancers

I love the Transatlantic Acoustic Show. It’s a chick from New York and a quirky Britishman exchanging witty banter and they play wonderful indie folk music. It’s one of the very few podcasts that I listen to.

Anyway, in one of their older shows (#56, from 12/8/2007), which I just listened to while driving back home from a conference, they talked about Morris dancing. They talked about how Youtube and parts of the internet could make people think that everyone in England is a Morris dancer and that men dancing with bells on their legs while hitting sticks together is as British as the Queen. Similarly, cowboys are the American icons that the media makes everyone else in the world think that cowboys are everywhere in America herding cattle.

Sadly, it’s neither the case that England is filled with Morris dancers and America is filled with cowboys. But wouldn’t it be awesome if those statements were true? Is there a correlation between people who think that cowboys are awesome and people who think that Morris dancers are awesome? Huh?

An Engagement in Reading

Today I went to the second half of the Exeter All Day Sing in the Exeter Friends Meetinghouse near Reading, PA. It was marvelous. For one thing, it was funny seeing all the familiar faces; it’s as if New England moved down to Reading for an afternoon. Towards the end there was a dance-level volume of stomping, but we sang over it anyway. It was also really hot (almost 40 degrees Celsius) but that didn’t really matter.

I led Russia (107). This is good because it’s been exactly one year since I first led a song (Holy Manna, which is 59, I think). That happened at the same all day sing. I’ve gotten noticeably better during the year. For example, I no longer forget where the altos are. Now, I’m sure that all but one or two of the altos there have been doing this much longer than I have and don’t need me to remind them that they come in after the tenors, but it’s just not nice to forget the altos.

The title of this post is only funny if you pronounce Reading correctly as “Redding”.

Bending a Line of Four

So let’s talk about that post with the diagram that I said had something to do with a contradance.

In the last week, caller and fiddler Amy Cann and I co-taught a seven-day-ish course called Patterns and Mathematics in Traditional Folk Dancing. It was basically a short, intensive workshop on analyzing contra and English country dances as mathematicians, dancers and choreographers. The goal was to use mathematics to help us become better dancers and choreographers. As part of the course, Amy solicited from a dance caller’s mailing list various caller’s lists of favorite and least favorite transitions. The diagram I had in the previous post is a still from an animation that illustrates a geometry problem that came from one of these transitions.

First, let’s look at the problem mathematically.

In the diagram above, we have segment a formed by points A and B and segment b formed by points C and D. The goal is to rotate segment a as one rigid object on to segment b so that point A rotates to point C and point B rotates to point D. In order to do that, we need the center of rotation. This is not a hard geometric problem; it takes some thinking, especially if your geometry is rusty, but it’s perfectly solvable using straightedge and compass in a few steps.(Side note: I proclaimed when giving this problem that I did not expect any of my students educated in the United States to be able to solve this problem. I was half right; two of our students solved this problem: one learned geometry in Germany and the other in a Waldorf school in the United States. Double side note: I’m considering sending my kids to Waldorf schools. Triple side note: I don’t have any kids yet and don’t really plan to have any.)

The fun part is where this problem came from!

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