Part 2 Krippner: The Great Debate: Einstein-Podolsky-Rosen Paradox and Non-locality

The Great Debate: EPR and Nonlocality
Schroll: Historically nonlocality’s spooky action-at-a-distance led to Einstein’s rejection of quantum theory, because this apparent instantaneous transmission of a signal violates Einstein’s special theory of relativity that states no object can travel faster than the speed of light. Physicist Bernard d’Espagnat has referred to the conceptual assumptions that we associate with this cosmic speed limit as Einstein locality (d’Espagnat, 1979, 1983). Yet, I say apparent because continued reflection to understand this problem has led to the view that the concept of nonlocality cannot be understood in terms of our everyday experience of movement or signal transmission (Bohm, 1984). Our complete discussion of this point exceeds this essay’s limits and has been taken up in greater detail in (Schroll, 2006b).
What needs to be said at this time is that the Einstein-Podolsky-Rosen paradox or EPR represents one of the greatest debates of science and philosophy, which began at the fifth Solvay congress in 1927. In addition to EPR’s previous criticisms that nonlocality appears to violate the special theory of relativity, the basis of this argument centers on Einstein’s firm conviction that the postulate of physical realism is true. It was Einstein’s dying-belief that an independent objective reality exists completely separate from the perceiving subject, and that this postulate should be the foundation of all natural science (Davies, 1983; d’Espagnat, 1979, 1983; Gribbin, 1984; and Herbert, 1985).
Contrary to EPR’s postulate of physical realism and Einstein locality, quantum theory states that because our universe is nonlocal it is impossible to accurately measure simultaneously the position and momentum of a subatomic particle. This idea is referred to as the Heisenberg Uncertainty Principle and serves as the cornerstone of the Copenhagen Interpretation of Quantum Mechanics, whereas the construction of the radioactive devices Stan talked about is also the result of John Stewart Bell’s contribution to our understanding of nonlocality.
In 1964, John Stewart Bell developed a mathematical formalism of the EPR paradox that has come to be known as Bell’s Inequality. Bell postulated that if his inequality was violated it would experimentally demonstrate that quantum theory is correct. To date, at least 13 experiments have been conducted to measure Bell’s inequality; of these, 11 have successfully registered a violation—thereby confirming quantum theory’s correctness. These experiments have also demonstrated something equally dramatic; they have proved that Einstein was wrong about quantum theory. God does play dice with the universe. My tally of experiments that have been performed to test Bell’s inequality relies on Alain Aspect and Philippe Grangier’s (1986) essay “Experiemnts on Einstein-Podolsky-Rosen-type Correlation’s with Pairs of Visible Photons”, and Abner Shimony’s (1989) essay “Search for a Worldview Which Can Accommodate Our Knowledge of Microphysics.”