Physicist — Alain Aspect (Agen, 1947) is a French physicist, a leading figure in experimental quantum physics. In the early 1980s he carried out a series of refined experiments on entangled photon pairs that verified the violation of Bell’s inequalities, convincingly demonstrating that nature cannot be described by local hidden-variable theories. His results confirmed the predictions of quantum mechanics on entanglement, ruling out the classical view defended by Einstein in the famous EPR paradox. This work paved the way for modern quantum information technologies, such as quantum cryptography and computing. For these contributions he received the Nobel Prize in Physics in 2022, together with John Clauser and Anton Zeilinger.
Trivia
Aspect’s key 1982 experiment used ultra-fast optical switches that changed the detectors’ orientation while the photons were already in flight, in order to rule out any communication between them and close a possible loophole in the Bell test.
Theories and contributions
- Verification of Bell’s inequalities — Experiments on entangled photons showing , in agreement with quantum mechanics and against local hidden-variable theories.
- Quantum entanglement — Two correlated particles show measurement results statistically linked even at great distance, with no local classical explanation.
Present in chapters
Linked atoms
2 linked atoms.