Entanglement was first clearly described, and named, in 1935, by the Austrian physicist Erwin Schrödinger. He pointed out that,
after two quantum particles interacted, they could no longer be considered independent of each other, as classical physics would have allowed. As the contemporary US physicist Leonard Susskind puts it in the preface to Quantum Mechanics: The Theoretical Minimum (2014), ‘one can know everything about a system and nothing about its individual parts.’
https://aeon.co/essays/our-simple-magic-free-recipe-for-quantum-entanglement
