Here's s much more well-written release:
http://news.mit.edu/2018/physicists-crea...light-0215

Here's one part I thought was interesting:

Quote:While photons normally have no mass and travel at 300,000 kilometers per second (the speed of light), the researchers found that the bound photons actually acquired a fraction of an electron’s mass. These newly weighed-down light particles were also relatively sluggish, traveling about 100,000 times slower than normal noninteracting photons.

The question is where did it acquire the mass? Did it somehow take it from something in the cloud? Is it even a "new form of light" if it has mass?