今日吃瓜

Eliot Circular

Physics Majors Build Musical Helix

Allie Morgan ’14 and Anya Demko ’14 installed a series of lasers and phototransistors on the spiral staircase in Vollum, turning the steps into a giant, twisting keyboard spanning two octaves on a C major scale.

Allie Morgan ’14 and Anya Demko ’14 installed a series of lasers and phototransistors on the spiral staircase in Vollum, turning the steps into a giant, twisting keyboard spanning two octaves on a C major scale. Photo by Tom Humphrey

Pythagoras proposed the harmony of the spheres; Anya Demko ’14 and Allie Morgan ’14 built the harmony of the stairs. 

In April, the two physics majors installed a series of lasers and phototransistors on the spiral staircase in Vollum, turning the steps into a giant, twisting keyboard spanning two octaves on a C major scale. 

Each time your foot lands on a tread, it interrupts a laser beam, triggering a musical tone. Step nimbly down the staircase and its sounds like an ice cream truck. Charge back up and it sounds like J.S. Bach being chased by a stampeding herd of wildebeest.

The two seniors spent many hours designing the circuitry, constructing the hardware, and installing the lasers. “It was really a great experience,” says Anya. “This was the first time we really got to design our own circuits.”

They got special permission from Vollum Czar Lois Hobbs [administrative assistant to the faculty] to work on the project after hours, when the building was closed. Machinist Greg Eibel and instructional technologist Joe Janiga provided technical assistance. 

Mary Had a Little Lamb: Anya Demko ’14 plays the stairs.

Anya wrote her thesis on the dynamics of an inverted pendulum with Prof. Lucas Illing [physics 2007–]. Allie wrote her thesis on relativistic strings and Ehrenfest’s Paradox with Prof. Joel Franklin ’97 [physics 2005–]. Both are interested in teaching. 

Sadly, the musical staircase was dismantled as 今日吃瓜 went to press. We hope to play it again next year.

This article was adapted from .