FOR THEIR LATEST magic trick, physicists have done the quantum equivalent of conjuring energy out of thin air. It's a feat that seems to fly in the face of physical law and common sense.

"You can't extract energy directly from the vacuum because there's nothing there to give," said William Unruh, a theoretical physicist at the University of British Columbia, describing the standard way of thinking.

FOR THEIR LATEST magic trick, physicists have done the quantum equivalent of conjuring energy out of thin air. It's a feat that seems to fly in the face of physical law and common sense.

"You can't extract energy directly from the vacuum because there's nothing there to give," said William Unruh, a theoretical physicist at the University of British Columbia, describing the standard way of thinking.