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Alain Aspect Ph D thesis

Alain Aspect ``Three experimental tests of Bell inequalities by the measurement of polarization correlations between photons''
Ph. D thesis defended in Orsay (France) on feb 1st, 1983.
The jury was composed as follows:
A. Marechal, J.S. Bell, C. Cohen-Tannoudji, B. d'Espagnat, C. Imbert, F. Laloe
The J.S. Bell of the Jury is THE J.S. Bell of Bell inequalities and C. Cohen-Tannoudji recently awarded the Nobel Prize in Physics (and also he wrote a graduate-level book about Quantum Mechanics which is (as for me) the best book on this topic so-far).
Also d'Espagnat and the others are well known in the world of Quantum Mechanics and the problems of its interpretation.
That's a jury, isn't it !!!!!!

The experimental setup uses a calcium source (in an atomic jet), lightened by a kripton laser and an argon laser. Then the produced photons come from the cascade :
(4p2 1S0)->(4s4p 1P1)->(4s2 1S0)
( A. Aspect, C. Imbert, G. Roger, ``Absolute Measurement of an atomic cascade rate using a two-photon coincidence technique. Application to the (4p2 1S0)->(4s4p 1P1)->(4s2 1S0) cascade of calcium exited by a two photon absorption'', Optics Communication 34 (1980) p46. )

The results of the experiment

The Bell-Freedman inequality say that Delta <=0. The experimental measurement leads to :
Delta = 0.064 +/- 0.009
Quantum Mechanics expects the following result :
Delta = 0.059

The BCHSH inequality states that S'<=0. The experimental measurement leads to :
S' = 0.1 +/- 0.02
Quantum Mechanics gives the value :
S' = 0.12

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