# Mathematical Impressions: Long Sword Dancing

Traditional long sword dancing is an art form that produces stable patterns of interwoven segments. These structures, sometimes called “popsicle stick bombs,” are surprisingly rich mathematically and raise subtle difficulties for those attempting to analyze their stability. Dancers look for sequences of movements that will produce a desired configuration, an algorithmic question that is particularly challenging if the arms and swords are required to maintain a simple closed loop during the dance.

The standard reference on traditional dances is Ivor Allsop, “Longsword Dances from Traditional and Manuscript Sources” (Northern Harmony, 1996).

For a stability analysis, see Walter Whiteley, “Rigidity and Polarity II: Weaving Lines and Tensegrity Frameworks,” Geometriae Dedicata 30, no. 3 (1989), pp. 255-279.

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• Lee says:

Fascinating! Never heard of this before, but leave it to Mr. Hart to come up with something clever and surprising.

• A very interesting piece of work.

Will there be a companion piece on rapper sword dancing? It’s the cousin linked sword tradition from the NE of England.

Sword Dance Union members would be very interested in seeing this! Would I be OK to post this on our news/blog page? Properly referenced and linked etc.

Thanks

Edwin

• Thomas Lin says:

@Edwin: Glad you liked George’s video. You’re welcome to reference and link to this on your blog.

• Trevis says:

How ’bout Khachaturian’s _Sabre Dance_? This should surely include (by my mental count) a 15-gon, at the very least!

• Elizabeth says:

I found these looping dance maneuvers to be fascinating in modeling how “particle structure” can arise from 2 dimensional fields in 3 dimensions – not quite knots, but stable through space-time 😀