The possibility of creating actual lightsabers inched closer to reality with the discovery that three light particles can be bound together, raising scientific and legal questions unseen since the Old Republic.

But unlike the crystal-powered plasma blades of “Star Wars,” news surfaced this month that a team of Harvard University and Massachusetts Institute of Technology scientists was able to bind photons by shining a laser through a cloud of rubidium, the metallic element below potassium on the periodic table.