Quantum entanglement by classical computer: a crucial experiment
Luigi Accardi, Centro V. Volterra, Roma
A simple experiment is described in which two experimenters, by performing independent, local, binary choices on a common classical, deterministic, macroscopic source of randomness (in fact a generator of random points in the unit disk in the plane) and computing the empirical correlations among their results, arrive to a violation of Bell's inequalities. The local binary choices satisfy all the standard conditions of the EPR experiment: singlet, equiprobability, rotation invariance, etc.
In addition the experiment suggests a new interpretation of the usual EPR experiment, more natural and appealing from the physical point of view than the usual one and totally in line with the "chameleon effect" which is at the basis of the quantum probabilistic approach to the theory of quantum measurement.
A mathematical formulation of the "chameleon effect" will be discussed and illustrated with the mathematical model used to write the computer programme used in the experiment. The result of the present experiment, which for a long time has been considered to be impossible by the majority of physicists, fully confirms the point of view advocated, starting from the late 70's, by quantum probability in absolute isolation and strongly opposed by the majority of physicists who, following the interpretation due to Bell, were relating the violation of Bell's inequality to a non locality effect.
In particular the experiment proves that:
(i) it is possible to produce non-Kolmogorovian correlations by local realistic classical deterministic macroscopic systems
(ii) it is possible to produce quantum entanglement by classical
This opens the way to a series of new possibilities, for example the possibility of implementing quantum cryptography by classical computer. The experiment will be described and performed during the talk and the public will have the possibility to check the procedure by choosing the parameters of the measurements. An earlier version of the experiment is available at the Volterra Institute.