Self-similar blow-up patterns for a reaction-diffusion equation with weighted reaction in general dimension

We classify the finite time blow-up profiles for the following reaction-diffusion equation with unbounded weight: ∂tu = ∆u^m + |x|^σu^p, posed in any space dimension x ∈ R^N , t ≥ 0 and with exponents m > 1, p ∈ (0, 1) and σ > 2(1−p)/(m−1). We prove that blow-up profiles in backward self-simil...

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Detalles Bibliográficos
Autores: Iagar, Razvan Gabriel, Muñoz Montalvo, Ana Isabel, Sánchez, Ariel
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universidad Rey Juan Carlos
Repositorio:BURJC-Digital. Repositorio Institucional de la Universidad Rey Juan Carlos
OAI Identifier:oai:burjcdigital.urjc.es:10115/26800
Acceso en línea:https://hdl.handle.net/10115/26800
Access Level:acceso abierto
Palabra clave:Reaction-diffusion equations
weighted reaction
blow-up
self-similar solutions
phase space analysis
strong reaction.
Descripción
Sumario:We classify the finite time blow-up profiles for the following reaction-diffusion equation with unbounded weight: ∂tu = ∆u^m + |x|^σu^p, posed in any space dimension x ∈ R^N , t ≥ 0 and with exponents m > 1, p ∈ (0, 1) and σ > 2(1−p)/(m−1). We prove that blow-up profiles in backward self-similar form exist for the indicated range of parameters, showing thus that the unbounded weight has a strong influence on the dynamics of the equation, merging with the nonlinear reaction in order to produce finite time blow-up. We also prove that all the blow-up profiles are compactly supported and might present two different types of interface behavior and three different possible good behaviors near the origin, with direct influence on the blow-up behavior of the solutions. We classify all these profiles with respect to these different local behaviors depending on the magnitude of σ. This paper generalizes in dimension N > 1 previous results by the authors in dimension N = 1 and also includes some finer classification of the profiles for σ large that is new even in dimension N = 1.