Updated November 23, 2021 at 11:02 AM ET
If you've ever seen the Marvel movie Avengers: Infinity War, you probably recall the scene where antagonist Thanos has all the Infinity Stones in his metal glove, and with a snap of his fingers he wipes out half of the population of the universe.
That scene sparked some off-camera drama at the Georgia Institute of Technology where biophysicist Saad Bhamla was skeptical about the realities of snapping with a glove on.
"I was like, no way can that Thanos snap with that Infinity Gauntlet," Bhamla says. "I bet, like, the softness of our skin has something to do with it."
Bhamla co-authored a new study of finger snapping that was published last week by The Royal Society. He says the sound of snapping is fairly easy to explain.
"If I snap my fingers, the sound is originating when your finger actually slams into the fleshy part of your thumb or your hand," he says.
But Bhamla and his team wanted to know more about the physics involved, so they put sensors on their fingers and then snapped with rubber gloves on, with lotion on and with metal thimbles on their fingertips.
As they tested the different variables, they filmed high-speed video. After analyzing the footage, the scientists determined that skin to skin friction along with the compressibility of our fingers is key to generating the motion.
Which means it won't work in a metal glove. Sorry, Thanos. They also found that the whimsical ability of snapping is really, really fast.
"The angular accelerations are about 1.6 million degrees per second squared," Bhamla says.
That's about 20 times faster than the blink of an eye, and even faster than the arm movement of a pro baseball pitcher, which, Bhamla says, was considered one of the fastest rotational motions a human body is capable of — until now that is.
"Us, you know, these scientists who are by no means any athletes — we barely go to the gym — and we are snapping our fingers and breaking the records of these professional athletes," Bhamla says.
So perhaps it's time to retire the saying "faster than the blink of an eye," and start using "faster than the snap of a finger."
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