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arXiv · 1809.09950

Global bifurcation index of critical orbit of strongly indefinite functional

Anna Gołębiewska·Piotr Stefaniak
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Abstract

In this paper we study an index of a critical orbit, defined in terms of the degree for invariant strongly indefinite functionals. We establish a relationship of this index with the index of a critical point of the mapping restricted to the space normal to the orbit. The second aim of the article is to use the index of a critical orbit to prove the bifurcation of nontrivial solutions of nonlinear elliptic systems with Neumann boundary conditions. We consider also the existence of unbounded sets of solutions of such systems.

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Anna Gołębiewska, Piotr Stefaniak. 2018-09-26. Global bifurcation index of critical orbit of strongly indefinite functional. https://arxiv.org/abs/1809.09950

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