(<small>French pronunciation</small>: ; born 15 June 1947 in Agen
) is a French physicist
and alumnus of the École Normale Supérieure de Cachan
(ENS Cachan) in France. In the early 1980s, while working on his PhD thesis from the lesser academic rank of lecturer, he performed the elusive "Bell test experiments
" that showed that Albert Einstein, Boris Podolsky and Nathan Rosen's reductio ad absurdum of quantum mechanics, namely that it implied 'ghostly action at a distance', did in fact appear to be realised when two particle
were separated by an arbitrarily large distance. A correlation
between their wave functions
remained, as they were once part of the same wave-function that was not disturbed before one of the child particles was measured.
If quantum theory is correct, the determination of an axis direction for the polarization
measurement of one photon, forcing the wave function to 'collapse' onto that axis, will influence the measurement of its twin. This influence occurs despite any experimenters not knowing which axes have been chosen by their distant colleagues, and at distances that disallow any communication between the two photons, even at the speed of light.
Aspect's experiments were considered to provide overwhelming support to the thesis that Bell's inequalities
are violated in its CHSH
version. However, his results were not completely conclusive, since there were so-called loopholes
that allowed for... Read More