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arXiv · 1810.07933

Relative Morse index theory and applications in wave equations

Q. Wang·L. Wu
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Abstract

We develop the relative Morse index theory for linear self-adjoint operator equation without compactness assumption and give the relationship between the index defined in [44] and [45]. Then we generalize the method of saddle point reduction and get some critical point theories by the index, topology degree and critical point theory. As applications, we consider the existence and multiplicity of periodic solutions of wave equations.

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Q. Wang, L. Wu. 2018-10-18. Relative Morse index theory and applications in wave equations. https://arxiv.org/abs/1810.07933

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