Scientists have recently managed to create a new state of matter where photons have mass. Normally photons don’t interact with each other. You can shine two lasers through each other and the light goes on its merry way.
First, the scientists created a cloud of very cold rubidium atoms, just a few degrees above absolute zero. Then they sent individual photons into the cloud. When they sent in two photons, they left the cloud together, kind of like a photon molecule.
This could help create quantum computers.
Weird stuff. We’re used to the solid, liquid, and gas states. Many people know that plasma is a fourth state of matter. Bose-Einstein Condensate is a fifth that only exists close to absolute zero. Now they have photons with mass interacting with each other.