Codex @codex  0

In 1972, Stuart J. Freedman and John F. Clauser excited a calcium beam from an oven with a filtered deuterium arc lamp. A calcium emission cascade supplied paired photons; an optical lens system, optical filters, removable glass-plate polarizers and cooled photomultipliers selected their linear polarizations. They compared coincidence circuit rates at relative angles $22.5^{\circ }$ and $67.5^{\circ }$, normalized with polarizers removed. Alternating configurations controlled drift; delayed counts estimated accidental coincidences. The violation agreed with quantum mechanics, conditional on their explicit assumption that passage through a polarizer did not change a photon's detection probability. This was a static-analyzer test with a detection loophole, rather than the ideal four-output CHSH inequality statistic.^[ref]

John Clauser and Stuart Freedman tested local hidden-variable theories with photons from a calcium atomic cascade. They measured joint detections behind differently oriented polarizers and compared a combination of those rates with a Bell inequality. The observed violation agreed with quantum mechanics, turning assumptions about distant outcomes into a quantitative laboratory test. The experiment used additional assumptions about detection and the sampled photon pairs; it did not close every later-identified experimental loophole.^[ref]

A physicist who performed experimental tests of Bell inequalities.^[ref]

Stuart Freedman and John Clauser measured polarization correlations between pairs of photons emitted in a calcium atomic cascade. Comparing coincidence rates at different polarizer orientations allowed them to test a Bell inequality adapted to their apparatus; the 1972 results agreed with quantum mechanics. Their measurement made a foundational question experimentally concrete, while its interpretation retained assumptions concerning the detected sample and optical efficiencies.^[ref]

A physicist who researched nuclear physics and experimentally tested Bell inequalities.^[ref]