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arXiv · 1601.01543

A computer-assisted existence proof for Emden's equation on an unbounded L-shaped domain

Abstract

We prove existence, non-degeneracy, and exponential decay at infinity of a non-trivial solution to Emden's equation $-Δu = | u |^3$ on an unbounded $L$-shaped domain, subject to Dirichlet boundary conditions. Besides the direct value of this result, we also regard this solution as a building block for solutions on expanding bounded domains with corners, to be established in future work. Our proof makes heavy use of computer assistance: Starting from a numerical approximate solution, we use a fixed-point argument to prove existence of a near-by exact solution. The eigenvalue bounds established in the course of this proof also imply non-degeneracy of the solution.

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BibTeXRIS

Filomena Pacella, Michael Plum, Dagmar Rütters. 2016-01-07. A computer-assisted existence proof for Emden's equation on an unbounded L-shaped domain. https://arxiv.org/abs/1601.01543

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