Particles of light—photons—that are forced to interact with each other through specially structured glass demonstrate behavior evocative of the "fractional quantum Hall effect," a phenomenon that garnered the 1998 Nobel Prize in physics when demonstrated with electrons. A team of researchers at Penn State has now demonstrated that the movement of light from an extremely powerful laser becomes "fractionalized" as it passes through the glass, an emergent property that adds to our fundamental understanding of physics that emerges from complex environments.