A sitter to start off the week… Which famous experiment is depicted here?

Cracked by Tathagata Chatterjee , sidsen , Dibyo , Rohan , Goyal , insufferablejake , piezocake , Guneet , Vinay , Ananth , VikraM , Sujay , gudanggurum (copy-pasta is not required, mate), Atul Mathew , Nakul , Chandrakant Nair , malcaluffin , duriel , rajeshvj and Prasad; or, in short, almost everyone.

Tathagata Chatterjee, sidsen, Dibyo, Rohan, Goyal, insufferablejake, piezocake, Guneet, Vinay, Ananth, VikraM, Sujay, Gurupad, Atul Mathew, Nakul, Chandrakant Nair, malcaluffin, duriel, rajeshvj and Prasad