STABILITY OF COSMOLOGICAL DETONATION FRONTS

We present results of a linear stability analysis of relativistic deto nation fronts, which have been considered as representing phase interf aces in cosmological first-order phase transitions: After discussing g eneral stability conditions for detonation fronts, we concentrate on t he properties of the fronts with respect to corrugation instabilities and discuss separately the cases of Chapman-Jouguet and strong detonat ion waves. Contrary to what is recently claimed, we find that strong d etonations are both evolutionary and stable with respect to corrugatio ns of the front. Moreover, Chapman-Jouguet detonations appear to be un conditionally linearly stable. The implications of the stability resul ts for first-order cosmological phase transitions are presented and a discussion of the causal structure of reaction fronts is also given.