Thermonuclear Explosions of White Dwarfs: What have supernova explosions and combustion engines in common?

Because calibrated light curves of thermonuclear (Type Ia) supernovae

have become a major tool to determine the local expansion rate of the

Universe, and also its geometrical structure,

considerable attention has been given to models of these events

over the past couple of years. There are good reasons to believe

that perhaps most Type Ia supernovae are the explosions of white dwarf

stars, consisting mainly of carbon and oxygen only, that

have approached the Chandrasekhar mass,

M_chan 1.39 M,

and are disrupted by thermonuclear fusion of carbon and oxygen. Recent progress in modeling Type Ia supernovae as well as several of the still open questions are addressed in this talk. Although the main emphasis will be on studies of the explosion mechanism itself and on the related physical processes, including the physics and numerical modeling of turbulent nuclear combustion in degenerate stars, we also discuss observational implications and constraints, including consequences for cosmology.