Quantum mechanics is real. It's spooky as hell, but it's real. Without its microscopically small probabilistic effects, we wouldn't have superconductors, lasers, and many forms of computing and cryptography. But despite our laboratory certainty, what's less clear is the role it plays in the fundamental nature of reality. And as a recent survey published by Anton Zeilinger at the University of Vienna has revealed, quantum physicists are still very divided on how it's to be interpreted.
The poll had 16 multiple choice questions and was filled out by 33 participants attending the Quantum Physics and the Nature of Reality conference in Austria in 2011. Technology Review reviews the answers, showing the utter lack of consensus:
For example, in answer to the question "Do you believe that physical objects have their properties well defined prior to and independent of measurement?", 48 per cent replied "no", while 52 per cent replied "yes, in some cases". A further 3 per cent said "yes in all cases" and 9 per cent were undecided (respondents were able to select more than one answer).
The question "What is your favourite interpretation of quantum mechanics?" had 12 possible answers. The most popular answer was the Copenhagen interpretation with 42 per cent but 18 per cent chose the many-worlds interpretation. 21 per cent admitted to having switched their interpretation several times with one respondent writing that he sometimes switched interpretations several times a day.
The question "When will we have a working and useful quantum computer?" drew an interesting spread of responses. Only 9 per cent thought this would be possible within 10 years while 15 per cent said never. The answer "In 10-25 years" drew 42 per cent of the respondents while "In 25-50 years" drew 30 per cent.
Interestingly, there was some agreement. More than two-thirds believed that there is no fundamental limit to quantum theory, and that it should be possible for objects — no matter how big — to retain their applicability to quantum superpositions like Schrödinger's cat. This is a fairly important development, as survey co-author Maximilian Schlosshauer points out: "So the era where quantum theory was associated only with the atomic realm appears finally over."
Image: Shutterstock/ l i g h t p o e t.