Anyone who has ever tried to forget a bad night knows that erasing memory takes work. Physicists have now shown this is literally true, by measuring the heat released when a single bit of information is deleted.
The discovery confirms a 1961 prediction by IBM physicist Rolf Landauer. It links information and heat flow in ways that keep the universe from breaking the second law of thermodynamics. Elaborations on Landauer’s idea may also prove useful in building miniature computers that don’t overheat.
“Here you have two quantities which seem to have nothing to do with each other, at least at first sight, and Landauer tells you that they are interconnected,” says physicist Eric Lutz of the Free University Berlin. “That’s a big deal.”
Lutz and his colleagues, from the universities of Kaiserslautern and Augsburg in Germany and a research lab in Lyon, France, describe the findings in the March 8 Nature.