One of the weirdest predictions of quantum mechanics is that the vacuum of space isn’t really empty. Because of the uncertainty principle, quantum theory predicts that a constant foam of “virtual particles” is flitting in and out of existence inside the void. Even weirder, these virtual particles can have real effects. This week, a paper in Nature demonstrates just such an effect: if you jiggle a mirror very close to the speed of light, you can turn pairs of virtual light particles into real ones.
The work was done by Christopher Wilson and a group based at the Chalmers University of Technology in Sweden. Rather than trying to vibrate a real mirror at near light speed, the team tweaked a superconducting circuit to create a wiggling, mirror-like electrical surface. We first wrote about the experiment when it appeared on the pre-print server arXiv.org, and you can read our original story here.
You can also listen to an interview I did with Wilson for this week’s Nature podcast.
By the way, for anyone wondering, making light out of nothing doesn’t violate the first law of thermodynamics. That’s because it takes far more energy to move the mirror than you ever get out in the form of light particles.
Credit: Wikipedia/Z. Le Zouave