Scholes uses multidimensional ultrafast and coherence spectroscopies to probe wavepacket dynamics and quantum-mechanical phenomena in photosynthetic light-harvesting complexes, cavity QED, and photo-activated chemistry, including his group's resolution of a decade-long controversy over long-lived coherent coupling in the Fenna-Matthews-Olson complex. His current work extends coherence spectroscopy to quantum information science and photobiomodulation, squarely fitting the fundamental light-physics/quantum-optics side of the filter.