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Travelling-waves for the FKPP equation via probabilistic arguments

Published online by Cambridge University Press:  14 November 2011

Simon C. Harris
Affiliation:
Department of Mathematical Sciences, University of Bath, Bath BA2 7AY, UK

Abstract

We outline a completely probabilistic study of travelling-wave solutions of the FKPP reaction-diffusion equation that are monotone and connect 0 to 1. The necessary asymptotics of such travelling-waves are proved using martingale and Brownian motion techniques. Recalling the connection between the FKPP equation and branching Brownian motion through the work of McKean and Neveu, we show how the necessary asymptotics and results about branching Brownian motion combine to give the existence and uniqueness of travelling waves of all speeds greater than or equal to the critical speed.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1999

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