User:Udon Nomaneim/Draft:Aspect's experiment

Aspect's experiment was the first quantum mechanics experiment to demonstrate the violation of Bell's theorem. Its irrefutable result allowed for further validation of the quantum entanglement and locality principles. It also offered an experimental answer to Albert Einstein, Boris Podolsky and Nathan Rosen's EPR paradox which had been proposed about fifty years earlier.

The experiment was led by French physicist Alain Aspect at the École supérieure d'optique in Orsay between 1980 and 1982. Its importance was immediately recognized by the scientific community, and made the cover of Scientific American, a popular science journal. Although the methodology carried out by Aspect presents a potential flaw, the detection loophole, his result is considered decisive and led to numerous other experiments which confirmed Aspect's original experiment.

Quantum entanglement
Quantum entanglementQuantum entanglement is a phenomenon first theorized by Erwin Schrödinger in 1935.

Quantum mechanics dictates that once two separate quantum systems (two particles for example) have interacted or if they have a common origin, they cannot be considered as two independent systems. The quantum mechanical formalism postulates that if a first system possesses a $$|\psi\rangle$$ state, and the second a $$|\phi\rangle$$state, then the resulting entangled system is represented by a quantum superposition of the tensor product of both states: $$|\psi\rangle|\phi\rangle$$. This notation lets shows clearly that the physical distance between the two systems plays no role in the entangled state (because no position variable is present). The entangled quantum state remains identical — all else being equal  — whatever the distances between both systems.