Asymptotic behaviour of the density in a parabolic SPDE

Consider the density of the solution $X(t, x)$ of a stochastic heat equation with small noise at a fixed $t \in[0, T], x \in[0,1]$. In this paper we study the asymptotics of this density as the noise vanishes. A kind of Taylor expansion in powers of the noise parameter is obtained. The coefficients...

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Detalles Bibliográficos
Autores: Kohatsu, Arturo, Márquez, David (Márquez Carreras), Sanz-Solé, Marta
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2001
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/216655
Acceso en línea:https://hdl.handle.net/2445/216655
Access Level:acceso abierto
Palabra clave:Grans desviacions
Càlcul de Malliavin
Equacions diferencials estocàstiques
Equacions diferencials parabòliques
Large deviations
Malliavin calculus
Stochastic differential equations
Parabolic differential equations
Descripción
Sumario:Consider the density of the solution $X(t, x)$ of a stochastic heat equation with small noise at a fixed $t \in[0, T], x \in[0,1]$. In this paper we study the asymptotics of this density as the noise vanishes. A kind of Taylor expansion in powers of the noise parameter is obtained. The coefficients and the residue of the expansion are explicitly calculated. In order to obtain this result some type of exponential estimates of tail probabilities of the difference between the approximating process and the limit one is proved. Also a suitable iterative local integration by parts formula is developed.