Watch this video of two musicians playing a two-violin arrangement of Mozart's sonata in C major K 296. They reach for their instruments, grab their arches. One look and they're off --the voices of the instruments mingle, each answering the other. One suggests a new direction, the other takes the challenge and ups the ante, and down the new path they go, frolicking in the cascades of sound. Together they weave a web of pure, exhilarating structure. The mathematics of Mozart!
One of these players is a professional violinist, the other a particle physicist. Can you tell which is which? How can you tell?