It's just one part of a rather bizarre lecture students recorded on camera.
The unusual quantum physics lecture now has the Ivy League university investigating the incident.
The man in the spotlight, taking off his clothes, is Emlyn Hughes, a world-renowned Columbia University professor.
In the audience was a roomful of undergraduates who came to hear a lecture on physics.
Instead, Hughes put on a black shirt and black pants.
Then he placed blindfolds on two stuffed animals.
Moments later, someone else appeared onstage and attacks one of the toys with an enormous sword.
On a huge screen behind them, were the horrifying images of the 9/11 attacks and the face of Osama bin Laden.
Later, the students would see images of Hitler, the Nazis, and Josef Stalin.
After five minutes of this, the professor spoke for the first time.
"In order to learn quantum mechanics you have to strip to your raw, erase all the garbage from your brain, and start over again. Quantum mechanics. Nothing you have learned in your life up to now has in any way helped prepare you for this because everything you do in your everyday life is totally opposite to what you're going to learn in quantum mechanics," Hughes said.
Columbia freshman Sarah Thompson was in the audience and couldn't believe what she was seeing.
Many students Eyewitness News spoke to say the presentation was shocking, but irrelevant to physics.
Tuesday night, a university spokesman says academic freedom has its limits, "The freedoms traditionally accorded the faculty carry corresponding responsibilities. The appropriate academic administrators are currently reviewing the facts of this particular presentation."
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