arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2102.01501math.APcs.NAmath.NAmath.OC
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某些非线性扩散问题的计算机辅助证明

Computer-assisted proofs for some nonlinear diffusion problems

Maxime Breden

摘要:

在过去的三十年中,强大的计算机辅助技术已经发展,以验证形式为$Δu +f(u,\nabla u) = 0$的半线性椭圆问题的后验数值解。通过研究定义在数值解周围的一个精心选择的不动点问题,这些技术使得有可能证明解在数值解的一个显式(通常很小)邻域中的存在性。在这项工作中,我们开发了一个类似的方法,更广泛的系统,包括非线性扩散项的形式$ΔΦ(u)$。特别是,这使我们能够获得新的结果,从人口动力学的交叉扩散系统的稳定状态:(非三角形)SKT模型。我们还重新审视了计算机辅助证明的背景下,自动微分的想法,并提出了一种基于微分-代数方程的替代方法。

英文摘要:

In the last three decades, powerful computer-assisted techniques have been developed in order to validate a posteriori numerical solutions of semilinear elliptic problems of the form $Δu +f(u,\nabla u) = 0$. By studying a well chosen fixed point problem defined around the numerical solution, these techniques make it possible to prove the existence of a solution in an explicit (and usually small) neighborhood the numerical solution. In this work, we develop a similar approach for a broader class of systems, including nonlinear diffusion terms of the form $ΔΦ(u)$. In particular, this enables us to obtain new results about steady states of a cross-diffusion system from population dynamics: the (non-triangular) SKT model. We also revisit the idea of automatic differentiation in the context of computer-assisted proof, and propose an alternative approach based on differential-algebraic equations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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