Part 6/9:

Bell's Inequalities: Separating Reality from Illusion

To explore this philosophical conflict, physicist John Stewart Bell introduced a series of experiments aimed at testing local realism through what is known as Bell’s inequalities. These inequalities provide a predictive framework: if they are violated during entanglement experiments, then local hidden variables cannot explain the observed phenomena—implying the necessity of non-locality.

Bell's experiments, particularly those conducted by Alain Aspect in the 1980s, confirmed that the expected correlations between entangled particles indeed violated Bell's inequalities. Thus, while locality may be cast into doubt, what about realism? Can we still consider an objectively real universe unwritten by observation?