Quantum Mechanics Entanglement and Spooky Action at a distance

See the basic setup   The math derived here.

      ————– distance = X nanoseconds light velocity ————–     

Imagine you and a friend agree to go to separate locations and flip a coin and record on a clip board what you get.   Imagine afterward you get together and compare notes and see that the entire list is identical ? 

That is what essentially what happens when two entangled photons separate and they go through polarizers at the end of their paths. 

Video:  Bell's Inequality and Photon Entanglement Video

Interesting points of note in the video

• pop bottle bottom glasses on 70's guy!
• Eigenvalues of a quantum mechanical solution are what you can observe.  You never observe solutions that are combinations of eigenvalues.
• StarTrek looking test apparatus mock up.  Scotty would have felt at home fixing this bugger!
• Einstein did not like ghostly action at a distance.  EPR
• Assume quantum theory is incomplete: Look for a hidden variable. Photon pairs are emitted with a shared equal hidden parameter.
• Theories using hidden variables have been created that preserve locality and realism
• Experiments that only test perfect correlations do not force us to choose between quantum explanation and hidden variable method
• John Bell was the first person to show how to bring the two theories into conflict so they could be tested
• Testing perfect correlations are tantamount to looking at one sock and seeing it is blue and concluding the sock on the other foot is blue
• Imperfect correlations: set the target polarizers at unequal angles.
• Alain Aspect and company tested Bell's Theorem
• Tunable lasers were required for this test setup

 

Notes regarding entanglement for purposes of understand the math / mechanics

• http://pagesperso-orange.fr/eric.chopin/epr/aspect.htm
• experimental setup
• How the experiment works  
• Picture of the Calcium source
• The Calcium transition that is used to emit the correlated photons
• Picture of the Polarizers at one end of the experiment

 

Bell's Theorem: The Quantum Venn Diagram Paradox

The following video gives a good simple explanation

Alain Aspect Video Presentation