# Mathemusic videos go viral

A “recreational mathemusician,” Vi Hart created a YouTube video about doodling in math class that’s gone viral, reports the New York Times.

The video never shows her face, just her hands doodling in a notebook. She talks about binary trees, Hercules cutting off the heads of a mythical hydra (each severed neck grows two new heads, which is the essence of a binary tree), and a fractal pattern known as Sierpinski’s Triangle.

She did another about drawing stars (really about geometry and polygons). Then another about doodling snakes (which segues into graph theory, “a subject too interesting to be included in most grade-school curricula,” she says). And another about prime numbers. (“Remember, we use prime numbers to talk to aliens. I’m not making this up.”)

More than a million people have viewed her videos.

A computer science professor’s daughter, Hart majored in music in college and took no math classes. But she attended math conferences and collaborated on papers with an MIT professor, Erik D. Demaine, known for his origami creations.

She started as a recreational mathartist, spending a week carving fruit into polyhedrons, posting photographs and instructions on vihart.com.

Last summer, she became enamored of hyperbolic planes, mathematical surfaces that are typically represented as horse saddles or Pringles chips.

Whereas others make bracelets or necklaces out of beads, Ms. Hart constructed hyperbolic planes out of them. She painted images of hyperbolic planes. She dried slices of fruit, which warped into hyperbolic planes.

“It just wiggles all over the place,” she said of a hyperbolic plane. “People don’t think of it that way, as being like a wild and beautiful thing.”

The doodle video has brought in some revenue and job offers. And it’s drawn a new demographic, teenage girls.

“I just think that’s really awesome,” she said, “because you’ve got girls in middle school and high school who are suddenly enjoy mathematics and enjoying being a little nerdy and smart, and we need that.”

Hart isn’t sure about her next step, though her goal is to be an “ambassador of mathematics,” like the late Martin Gardner, who wrote a math column for Scientific American.

For the holidays, she took advantage of the musical side of her mathemusician identity, rewriting “The 12 Days of Christmas.”

For example, “On the fourth day of Christmas, my true love gave to me: the smallest possible number of sides on a polyhedron, the number of points that define a plane, the divisor of even numbers and any other number to the power of zero.”

Mathematical translation: polyhedrons have a minimum of four sides, three points define a plane, two is a divisor of all even numbers, and any number raised to the power of zero is one.

STEMposium, an April 1 event at the California Academy of Sciences in San Francisco, is holding a video contest to generate ideas on how to improve science, technology engineering and math learning in schools.

Students, teachers and anyone with an innovative idea can submit a 60-second video. Finalists could win up to \$5,000 in cash and prizes and will be featured at STEMposium.

For example, here’s Judah’s video and here’s John’s idea.

1. as a math teacher those were awesome. I used to do some of those in class too, but never tried to make sense of them…funny.

2. Darryl says:

“any number raised to the power of zero is one.” I choose zero as the number.

Zero raised to any number is zero. I choose zero as the number.

Notice any problem?

3. Cardinal Fang says:

Zero to the zeroth power is a special case. Some axiomatizations say it’s 1 (very handy for combinatorics). Some say it’s undefined. It’s definitely not equal to zero, though; that doesn’t work.