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arXiv · 1410.0051

Conservative parabolic problems: non-degenerated theory and degenerated examples from population dynamics

Olga Danilkina·Max O. Souza·Fabio A. C. C. Chalub
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Abstract

We consider partial differential equations (PDE) of drift-diffusion type in the unit interval, supplemented by either two conservation laws or by a conservation law and a further boundary condition. We treat two different cases: (i) uniform parabolic problems; (ii) degenerated problems at the boundaries. The former can be treated in a very general and complete way, much as the traditional boundary value problems. The latter, however, bring new issues, and we restrict our study to a class of forward Kolmogorov equations that arise naturally when the corresponding stochastic process has either one or two absorbing boundaries. These equations are treated by means of a uniform parabolic regularisation, which then yields a measure solution in the vanishing regularisation limit that is unique. Two prototypical problems from population dynamics are treated in detail.

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Olga Danilkina, Max O. Souza, Fabio A. C. C. Chalub. 2016-02-13. Conservative parabolic problems: non-degenerated theory and degenerated examples from population dynamics. https://arxiv.org/abs/1410.0051

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