A viscosity solution method for the spreading speed formula in slowly varying media
A viscosity solution method for the spreading speed formula in slowly varying media
In this paper, we consider reaction-diffusion-advection equations in slowly periodically oscillating media.We prove the existence of and we give explicit expressions of the asymptotic spreading speeds of invasion of the unstable state 0 in any direction, when the period of the invaded medium becomes infinitely large.The limiting spreading speeds involve …