Quantum thermometers usher in the big chill

摘要

In the quantum world, simply measuring temperature can cool things down.rnQuantum systems normally exist in a superposition of several states at once, but collapse into a single state when observed. Two years ago physicists came up with the prediction that gauging the temperature of quantum objects could cause this collapse to occur in a way that cooled the object. Now Gonzalo Alvarez of the National University of Cordoba in Argentina and his colleagues have put this prediction to the test.