A FAREWELL TO COPENHAGEN?
Date: Sunday, August 08, 2004 @ 13:06:44 GMT
by John G. Cramer (from The Alternate View):
This column is about experimental tests of the various interpretations of quantum mechanics. The question at issue is whether we can perform experiments that can show whether there is an "observer-created reality" as suggested by the Copenhagen Interpretation, or a peacockís tail of rapidly branching alternate universes, as suggested by the Many-Worlds Interpretation, or forward-backward in time handshakes, as suggested by the Transactional Interpretation? Until recently, I would have said that this was an impossible task, but a new experiment has changed my view, and I now believe that the Copenhagen and Many-Worlds Interpretations (at least as they are usually presented) have been falsified by experiment.
The physical theory of quantum mechanics describes the behavior of matter and energy at the smallest distances. It has been verified by more than 70 years of experiments, and it is trusted by working physicists and regularly used in the fields of atomic, nuclear, and particle physics. However, quantum mechanics is burdened by a dismaying array of alternative and mutually contradictory ways of interpreting its mathematical formalism. These include the orthodox Copenhagen Interpretation, the currently fashionable Many Worlds Interpretation, my own Transactional Interpretation, and a number of others.
Many (including me) have declared, with almost the certainty of a mathematical theorem, that it is impossible to distinguish between quantum interpretations with experimental tests. Reason: all interpretations describe the same mathematical formalism, and it is the formalism that makes the experimentally testable predictions. As it turns out, while this "theorem" is not wrong, it does contain a significant loophole. If an interpretation is not completely consistent with the mathematical formalism, it can be tested and indeed falsified. As we will see, that appears to be the situation with the Copenhagen and Many-Worlds Interpretations, among many others, while my own Transactional Interpretation easily survives the experimental test.
The experiment that appears to falsify these venerable and widely trusted interpretations of quantum mechanics is the Afshar Experiment. It is a new quantum test, just performed last year, which demonstrates the presence of complete interference in an unambiguous "which-way" measurement of the passage of light photons through a pair of pinholes. But before describing the Afshar Experiment, let us take a backward look at the Copenhagen Interpretation and Neils Bohrís famous Principle of Complementarity..."
Read the whole article at: www.analogsf.com
An interesting discussion on this topic at: www.solohq.com