Famed physicist Albert Einstein chose Pittsburgh to give his first major speech in the United States 88 years ago this week. Einstein, already a celebrity by 1934, spoke to the American Mathematical Society Conference at Carnegie Tech, now Carnegie Mellon University, in Oakland.

The physicist spoke in a theater that held only 400 people with another 600 trying unsuccessfully to get in.

“People clambered to see Einstein’s lecture because he was one of the world’s first rock stars,” Gregg Franklin, a professor of physics at CMU, wrote of the event. “In his words, Einstein’s famous E = mc2 equation tells us that ‘mass and energy are both manifestations of the same thing — a somewhat unfamiliar conception for the average mind.’”

PHOTO COURTESY OF THE JACOB RADER MARCUS CENTER OF THE AMERICAN JEWISH ARCHIVES, CINCINNATI, OHIO. AMERICANJEWISHARCHIVES.ORG

Einstein’s brief visit to campus produced the only known photograph of him standing in front of a blackboard with a variant of his famous equation. The photograph was taken from a balcony of the Little Theaters, now known as Kresge Theatre at CMU.

According to Fred Gilman, the former dean of the Mellon College of Science, Einstein’s visit was one of a series of connections between Carnegie Tech and members of the Manhattan Project, which developed the first atomic bomb.

Learn more about the city’s past at The Odd, Mysterious & Fascinating History of Pittsburgh Facebook page.