2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/153225In bistable systems, the stability of front structures often influences the dynamics of extended patterns. We show how the combined effect of an instability to curvature modulations and proximity to a pitchfork front bifurcation leads to spontaneous nucleation of spiral waves along the front. This effect is demonstrated by direct simulations of a FitzHugh-Nagumo (FHN) model and by simulations of order parameter equations for the front velocity and curvature. Spontaneous spiral-wave nucleation often results in a state of spatio-temporal disorder involving repeated events of spiral wave nucleation, domain spliting and spiral wave annihilation.10 pages. An HTML version of this article is at http://www.springer-ny.com/nst/nstarticles.html . Aric Hagberg: http://t7.lanl.gov/People/Aric/; Ehud Meron: http://www.bgu.ac.il/BIDR/research/staff/meron.html To appear in Nonlinear Science Today, 1996: http://www.springer-ny.com/nst/Pattern Formation and Solitonstext