Who are these people doing math with dry erase markers on glass? Why are they doing that? How does it make any sense? When did this become a trope?pic.twitter.com/rPtJM17KYi
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1) Room partitions contain windows
2) Absence of white boards
3) It works in the moment
4) It looks really cool afterward to bystanders and visitors:
"OH LOOK!
SCIENCE! 

"
My guess is that it was used in movies / TV first because it lets you show the character's face and the equation in the same shot, then everyone thought it looked cool so they started doing it IRL.
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