The dialog begins with a look at how an ancient tribe would search for intelligent civilizations.  Then it continues to look at how we search the cosmos for intelligent alien communications.
This paper explains the concept of Quantum Entanglement.  It gives you a basic understanding of what it is and how it works.
Why are we searching the stars for alien radio signals? 
Quantum Entanglement would allow communications across the cosmos at a rate 10,000 times faster than the speed of light.  We might as well be looking for smoke signals. 
I have also included the title of an article, the author and the issue date in Scientific American that has the plans that will allow you to build your own phase differentiator and measure the phase shift in a Quantum Entanglement experiment of your own.