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arXiv · 1805.10597

Nonlinear perturbations of evolution systems in scales of Banach spaces

Martin Friesen·Oleksandr Kutoviy
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Abstract

A variant of the abstract Cauchy-Kovalevskaya theorem is considered. We prove existence and uniqueness of classical solutions to the nonlinear, non-autonomous initial value problem \[ \frac{du(t)}{dt} = A(t)u(t) + B(u(t),t), \ \ u(0) = x \] in a scale of Banach spaces. Here $A(t)$ is the generator of an evolution system acting in a scale of Banach spaces and $B(u,t)$ obeys an Ovcyannikov-type bound. Continuous dependence of the solution with respect to $A(t)$, $B(u,t)$ and $x$ is proved. The results are applied to the Kimura-Maruyama equation for the mutation-selection balance model. This yields a new insight in the construction and uniqueness question for nonlinear Fokker-Planck equations related with interacting particle systems in the continuum.

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Martin Friesen, Oleksandr Kutoviy. 2019-04-20. Nonlinear perturbations of evolution systems in scales of Banach spaces. https://doi.org/10.1088/1361-6544%2Fab9dc9

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