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arXiv · 1312.3865

Sequences of weak solutions for fractional equations

Giovanni Molica Bisci
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Abstract

This work is devoted to study the existence of infinitely many weak solutions to nonlocal equations involving a general integrodifferential operator of fractional type. These equations have a variational structure and we find a sequence of nontrivial weak solutions for them exploiting the ${\mathbb{Z}}_2$-symmetric version of the Mountain Pass Theorem. To make the nonlinear methods work, some careful analysis of the fractional spaces involved is necessary. As a particular case, we derive an existence theorem for the fractional Laplacian, finding nontrivial solutions of the equation $$ \left\{\begin{array}{ll} (-Δ)^s u=f(x,u) & {\mbox{in}} Ω\\ u=0 & {\mbox{in}} \erre^n\setminus Ω. \end{array} \right. $$ As far as we know, all these results are new and represent a fractional version of classical theorems obtained working with Laplacian equations.

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Giovanni Molica Bisci. 2013-12-13. Sequences of weak solutions for fractional equations. https://arxiv.org/abs/1312.3865

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