Tue, 24 Apr 2007
Good Bye to Reality
A recent experiment in subatomic physics increases confidence that there are no "hidden variables" in subatomic physics.Markus Aspelmeyer, Anton Zeilinger and colleagues from the University of Viennahave now shown that realism is more of a problem than locality in the quantum world. They devised an experiment that violates an inequality proposed by physicist Anthony Leggett in 2003 that relies only on realism, and relaxes the reliance [in Bell's Theorem] on locality.
They found that, just as in the realizations of Bell's thought experiment, Leggett's inequality is violated Ð thus stressing the quantum-mechanical assertion that reality does not exist when we're not observing it. "Our study shows that 'just' giving up the concept of locality would not be enough to obtain a more complete description of quantum mechanics," Aspelmeyer told Physics Web. "You would also have to give up certain intuitive features of realism."
I think the article confuses hidden variables with realism. There are realistic interpretations of quantum mechanics, such as the many worlds interpretation, that do not rely on hidden variables. No one in physics takes hidden variables seriously, anyway. It would have been quite a shock if the experiment came out the other way. Still, quantum mechanics shows that the naive "common sense" view of reality is not only wrong, it is provably wrong.
