  This article presents a theory for the rupture of rubber. Unlike conventional
cracks, ruptures in rubber travel faster than the speed of sound, and consist
in two oblique shocks that meet at a point. Physical features of rubber needed
for this phenomenon include Kelvin dissipation and an increase of toughness as
rubber retracts. There are three levels of theoretical description: an
approximate continuum theory, an exact analytical solution of a slightly
simplified discrete problem, and numerical solution of realistic and fully
nonlinear equations of motion.
