All someone had to do was actually construct and perform Bell’s modified version of the EPR thought experiment, or another experiment along those lines involving entangled particles. If the results showed that Bell’s inequality was violated, quantum physics was safe but nature was nonlocal; if his inequality held, then quantum physics was wrong but nature could be local. Bell’s impossibility proof had taken the question of nonlocality out of the realm of debate and turned it into an experimental challenge. This proof, now known as Bell’s theorem, has rightly been called “the most profound
...more
