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arXiv · 2008.05740

Superlinear perturbations of the eigenvalue problem for the Robin Laplacian plus an indefinite and unbounded potential

Nikolaos S. Papageorgiou·Vicenţiu D. Rădulescu·Dušan D. Repovš
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Abstract

We consider a superlinear perturbation of the eigenvalue problem for the Robin Laplacian plus an indefinite and unbounded potential. Using variational tools and critical groups, we show that when $\lambda$ is close to a nonprincipal eigenvalue, then the problem has seven nontrivial solutions. We provide sign information for six of them.

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Nikolaos S. Papageorgiou, Vicenţiu D. Rădulescu, Dušan D. Repovš. 2020-08-13. Superlinear perturbations of the eigenvalue problem for the Robin Laplacian plus an indefinite and unbounded potential. https://doi.org/10.1007/s00025-020-01234-z

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