Existence and uniqueness of a sharp travelling wave in degenerate non-linear diffusion Fisher-KPP equations

In this paper we use a dynamical systems approach to prove the existence of a unique critical value c * of the speed c for which the degenerate density-dependent diffusion equation $u_t = [D(u)u_x]_x + g(u)$ has: 1. no travelling wave solutions for 0 < c < c *, 2. a travelling wave sol...

Full description

Bibliographic Details
Main Authors: Sánchez-Garduño, F, Maini, P
Format: Journal article
Published: 1994
_version_ 1797061764946329600
author Sánchez-Garduño, F
Maini, P
author_facet Sánchez-Garduño, F
Maini, P
author_sort Sánchez-Garduño, F
collection OXFORD
description In this paper we use a dynamical systems approach to prove the existence of a unique critical value c * of the speed c for which the degenerate density-dependent diffusion equation $u_t = [D(u)u_x]_x + g(u)$ has: 1. no travelling wave solutions for 0 < c < c *, 2. a travelling wave solution $u(x, t) = \phi(x - c^{*} t)$ of sharp type satisfying $\phi(-\infty) = 1$, $\phi(\tau) = 0$ $\forall \tau\geq\tau^{*}$; $\phi'(\tau^{*-}) = -c^{*}/D'(0),\phi'(\tau^{*+}) = 0$ and 3. a continuum of travelling wave solutions of monotone decreasing front type for each c > c *. These fronts satisfy the boundary conditions $\phi(–\infty) = 1$, $\phi'(–\infty)=\phi(+\infty) = \phi'(+\infty) = 0$. We illustrate our analytical results with some numerical solutions.
first_indexed 2024-03-06T20:35:57Z
format Journal article
id oxford-uuid:32a1c4a4-f60c-41ef-95d7-1ae8e7edfa50
institution University of Oxford
last_indexed 2024-03-06T20:35:57Z
publishDate 1994
record_format dspace
spelling oxford-uuid:32a1c4a4-f60c-41ef-95d7-1ae8e7edfa502022-03-26T13:15:16ZExistence and uniqueness of a sharp travelling wave in degenerate non-linear diffusion Fisher-KPP equationsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:32a1c4a4-f60c-41ef-95d7-1ae8e7edfa50Mathematical Institute - ePrints1994Sánchez-Garduño, FMaini, PIn this paper we use a dynamical systems approach to prove the existence of a unique critical value c * of the speed c for which the degenerate density-dependent diffusion equation $u_t = [D(u)u_x]_x + g(u)$ has: 1. no travelling wave solutions for 0 < c < c *, 2. a travelling wave solution $u(x, t) = \phi(x - c^{*} t)$ of sharp type satisfying $\phi(-\infty) = 1$, $\phi(\tau) = 0$ $\forall \tau\geq\tau^{*}$; $\phi'(\tau^{*-}) = -c^{*}/D'(0),\phi'(\tau^{*+}) = 0$ and 3. a continuum of travelling wave solutions of monotone decreasing front type for each c > c *. These fronts satisfy the boundary conditions $\phi(–\infty) = 1$, $\phi'(–\infty)=\phi(+\infty) = \phi'(+\infty) = 0$. We illustrate our analytical results with some numerical solutions.
spellingShingle Sánchez-Garduño, F
Maini, P
Existence and uniqueness of a sharp travelling wave in degenerate non-linear diffusion Fisher-KPP equations
title Existence and uniqueness of a sharp travelling wave in degenerate non-linear diffusion Fisher-KPP equations
title_full Existence and uniqueness of a sharp travelling wave in degenerate non-linear diffusion Fisher-KPP equations
title_fullStr Existence and uniqueness of a sharp travelling wave in degenerate non-linear diffusion Fisher-KPP equations
title_full_unstemmed Existence and uniqueness of a sharp travelling wave in degenerate non-linear diffusion Fisher-KPP equations
title_short Existence and uniqueness of a sharp travelling wave in degenerate non-linear diffusion Fisher-KPP equations
title_sort existence and uniqueness of a sharp travelling wave in degenerate non linear diffusion fisher kpp equations
work_keys_str_mv AT sanchezgardunof existenceanduniquenessofasharptravellingwaveindegeneratenonlineardiffusionfisherkppequations
AT mainip existenceanduniquenessofasharptravellingwaveindegeneratenonlineardiffusionfisherkppequations