The University of Washington physicist who once ran a crowdfunded experiment on backward causation is now weighing in with a potential solution to one of the longest-running puzzles in quantum mechanics.
John Cramer, a UW physics professor emeritus, teamed up with Caltech electrical engineer and physicist Carver Mead to put forward an explanation for how the indefinite one-and-zero, alive-and-dead state of a quantum system gets translated into a definite observation — a phenomenon known as wave function collapse.
“Up to now, the mechanism behind wave function collapse has been considered a mystery that is disconnected from established wave mechanics. The result has been that a large number of attempts to explain it have looked elsewhere,” Cramer told GeekWire in an email.
“In our work, we have discovered that wave function collapse, at least in a simple case, is implicit in the existing formalism,” he said, “as long as one allows the use of advanced as well as retarded electromagnetic potentials.”
In other words, the explanation requires accepting the possibility that time can flow backward as well as forward. And for some physicists, that might be too big of a quantum leap.
“Most people just don’t like the idea of having the kind of time symmetry that sort of implies that time isn’t strictly speaking a one-way street,” Cramer acknowledged during a phone interview.