Miesch studies the internal dynamics of stars, with particular emphasis on the Sun. Stellar interiors seethe with turbulent convection, magnetism, and shear (differential rotation) which together give rise to patterns of variability such as the 11-year sunspot cycle. Miesch confronts this complexity head-on with the help of high-resolution simulations on massively parallel supercomputers. Such simulations have provided unprecedented insights into the global-scale structure of solar and stellar convection, the origins of differential rotation (why does the Sun's equator spin faster than its poles?) and meridional circulation, and how stars build magnetic fields.