A young Obe-Wan Kenobi with his lightsaber in "Star Wars: Episode III Revenge of the Sith."
In the hands of Jedi masters, glowing lightsabers behave like polished steel blades. But when the rest of us Obi-Wannabes shine a laser on another laser, nothing happens.
For the first time, physicists have come close to changing that. Under exacting experimental conditions, they've bewitched photons, notoriously mass-less packets of light, into behaving more like solids than ever before, and seen them attract each other like atoms.
"That is the physics of lightsabers," Mikhail Lukin, a physicist at Harvard University who was part of the team, told NBC News.
Photons don't interact. After a laser beam — a string of evenly spaced photons — was shot through a mist of vaporized ultra-cold rubidium atoms, the physicists observed the photons leaving the chamber in pairs. Lukin and Co. take that as evidence that inside, the photons were pulling towards each other with a very real ... force.
Theoretical physicists have explained this odd, mass-like behavior of photons in the past, but Lukin and team are the first to observe photons pairing up. The force between them was "so strong that single photons [pulled] each other together to create molecules," Lukin said. The team's findings appeared in Nature this week.
Alas, they won't be building a lightsaber any time soon — the more realistic application for friendly photons is in super-fast computers. Photon interactions are "the cornerstone for building photonic quantum computers," Thibault Peyronel, a grad student at MIT who is also part of the team, told NBC News. So maybe, in the end, this discovery is more of a Trek thing.
More on Star Wars science: The other authors of "Attractive photons in a quantum nonlinear medium" are Ofer Firstenberg, Qi-Yu Liang, Alexey Gorshkov and Vladan Vuletić.
Nidhi Subbaraman writes about science and technology. You can follow her on Facebook, Twitter and Google+.
First published September 27 2013, 11:40 AM