Joshua Erlich entered the Small 111 lecture hall bearing three gas-filled balloons and a pair of light sabers, one red, one green.
It was Oct. 31, Halloween, and Erlich addressed his William & Mary students in full Darth Vader regalia, including the helmet mask.
“Are there any questions from last time?” Vader/Erlich intoned. “If you have no questions, I will pull them from your mind! With the Force!”
There were no questions; even the Force came up empty. But there were plenty of giggles from the students in PHYS 100, Great Ideas of Modern Physics, a course designed for William & Mary’s COLL curriculum.
Erlich is a professor of physics at William & Mary and has traditionally observed Halloween with a little scientific cosplay. He jettisoned the Vader mask after a few minutes, noting it was too hard to breathe while giving a brief lecture on the physics of the human voice.
Relying on the power of the Force, Erlich selected student Sam Dyer to play Luke Skywalker in the climatic duel/revelation scene from Star Wars. Oddly, the prescient qualities of the Force didn’t stop the professor from delivering what was possibly the galaxy’s most superfluous spoiler alert. Is there a physics student anywhere from Alderaan to Tatooine who hasn’t searched his or her feelings and come to know and accept Luke’s true parentage?
Sam/Luke came through an abbreviated light saber duel with both hands still attached, which was handy because he needed one to hold a script and another to manage a balloon of helium. Erlich/Vader had his own script and another balloon, this one filled with sulfur hexafluoride. His preliminary remarks had included an explanation of how inhalation of a heavier-than-air gas has exactly the opposite effect of helium on a human voice.
Erlich’s explanation also included a substantial “don’t try this at home” segment. “You can’t go around inhaling random gases,” he said. “You can die doing this.”
Even though sulfur hexafluoride is chemically inert, Erlich pointed out that SF6 needs to be forcibly expelled from the lungs, whereas helium and other lighter-than-air recreational gases just naturally float up and out.
Fortified by sulfur hexafluoride and helium, Erlich and Dyer recreated the famous “I am your father” scene to the edification of the entire class. After huffing out the remnants of the sulfur hexafluoride, Erlich told the class that he felt a little bad using SF6, as it’s such a harmful greenhouse gas.
But what do you expect from Darth Vader?