J. Cisternas et Mc. Depassier, COUNTEREXAMPLE TO A CONJECTURE OF GORIELY FOR THE SPEED OF FRONTS OF THE REACTION-DIFFUSION EQUATION, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics, 55(3), 1997, pp. 3701-3704
In a recent paper, Goriely [A. Goriely, Phys. Rev. Lett. 75, 2047 (199
5)] considers the one-dimensional scalar reaction-diffusion equation u
(t)=u(xx)+f(u), with a polynomial reaction term f(u), and conjectures
the existence of a relation between a global resonance of the Hamilton
ian system u(xx)+f(u)=0 and the asymptotic speed of propagation of fro
nts of the reaction-diffusion equation. Based on this conjecture an ex
plicit expression for the speed of the front is given. We give a count
erexample to this conjecture and present evidence indicative that it h
olds only for a particular class of exactly solvable problems.