In this detail of the 2017 painting That We May See in a Chamber Things That Are Not 6 by Kate Nichols, silver nanoparticles are laid atop glass. Today’s uses of metal nanoparticles go well beyond art. In their article starting on page 24 , Jennifer Dionne, Sahil Dagli, and Vladimir Shalaev describe the underlying physics behind using plasmonic and other nanophotonic resonances for sustainable chemical manufacturing and pathogen detection, among other practical applications. (Courtesy of Kate Nichols, artist, and Donald Felton, photographer.)