My research interests include solar and stellar astrophysics. Specifically, I study the heating and energization of particles in the solar corona, the acceleration of the solar wind, and waves and turbulence in all kinds of astrophysical plasmas. Understanding the hot, expanding outer atmosphere of the Sun is a necessary precursor to being able to predict the Sun's long-term effects on the Earth's climate and local space environment. Other research includes radiative transfer in stellar atmospheres, kinetic plasma physics, the dynamics of winds from rotating hot (O, B, Wolf-Rayet) stars, and nonradial stellar pulsations.