In this survey we discuss old and new results on the number of critical points of solutions of the problem
$ \begin{equation} \begin{cases} -\Delta u = f(u)&in\ \Omega\\ u = 0&on\ \partial \Omega \end{cases} \;\;\;\;\;\;\;\;(0.1)\end{equation} $
where $ \Omega\subset \mathbb{R}^N $ with $ N\ge2 $ is a smooth bounded domain. Both cases where $ u $ is a positive or nodal solution will be considered.
Citation: Massimo Grossi. On the number of critical points of solutions of semilinear elliptic equations[J]. Electronic Research Archive, 2021, 29(6): 4215-4228. doi: 10.3934/era.2021080
In this survey we discuss old and new results on the number of critical points of solutions of the problem
$ \begin{equation} \begin{cases} -\Delta u = f(u)&in\ \Omega\\ u = 0&on\ \partial \Omega \end{cases} \;\;\;\;\;\;\;\;(0.1)\end{equation} $
where $ \Omega\subset \mathbb{R}^N $ with $ N\ge2 $ is a smooth bounded domain. Both cases where $ u $ is a positive or nodal solution will be considered.
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