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Estimates for the Sobolev trace constant with critical exponent and applications

J. Fernandez Bonder·N. Saintier
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Abstract

In this paper we find estimates for the optimal constant in the critical Sobolev trace inequality $S\|u\|^p_{L^{p_*}(\partialΩ) \hookrightarrow \|u\|^p_{W^{1,p}(Ω)}$ that are independent of $Ω$. This estimates generalized those of [3] for general $p$. Here $p_* := p(N-1)/(N-p)$ is the critical exponent for the immersion and $N$ is the space dimension. Then we apply our results first to prove existence of positive solutions to a nonlinear elliptic problem with a nonlinear boundary condition with critical growth on the boundary, generalizing the results of [16]. Finally, we study an optimal design problem with critical exponent.

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J. Fernandez Bonder, N. Saintier. 2006-12-13. Estimates for the Sobolev trace constant with critical exponent and applications. https://doi.org/10.1007/s10231-007-0062-1

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