Michael Shay studies plasma physics using analytical theory and computer simulations. His work is applicable to a diverse set of phenomena: solar flares and coronal mass ejections on the sun, the Earth's magnetosphere and space weather, star formation in astrophysical molecular clouds and accretion disks, and laboratory experiments including laser plasmas and fusion devices. His research focuses on multiscale phenomena in which short scales (length and time) are intrinsically linked to long scales, making them extremely difficult to simulate using conventional brute force methods. Two multiscale processes he has studied include magnetic reconnection and turbulence; he has also pioneered research understanding how the two interact and reinforce each other. Prof. Shay has worked extensively with other scientists to compare his simulations with observations of plasma phenomena in space. His work has been compared with data collected from many satellites, including Wind, THEMIS-ARTEMIS, Cluster, Polar, and Parker Solar Probe.