NONEQUILIBRIUM POTENTIAL FOR A REACTION-DIFFUSION MODEL - CRITICAL-BEHAVIOR AND DECAY OF EXTENDED METASTABLE STATES

We study a piecewise linear version of a bistable reaction-diffusion m odel of an electrothermal instability: the Ballast model. Our aim is t o analyze the change in the relative stability of nonhomogeneous linea rly stable states as some parameters-boundary reflectivity and system size-are varied, as well as the critical-like behavior when some of th ese states coalesce. The analysis is carried out through the use of th e nonequilibrium potential or Lyapunov functional for this system, whi ch also allows us to study the decay of the metastable extended states .