
The authors develop critical point theory for nonsmooth potentials \(f\colon H^1_0(\Omega)\longrightarrow\mathbb{R}\) of the form \(f(u)=\frac{1}{2}\int_{\Omega}\sum\limits_{i,j=1}^na_{ij}(x,u)D_iuD_ju\,dx-\int_{\Omega}G(x,u)\,dx\). First, the corresponding deformation lemma is proved. Next, a saddle point theorem is proved for functionals defined on a product space.
saddle point theorem, deformation lemma, quasilinear equation, Abstract critical point theory (Morse theory, Lyusternik-Shnirel'man theory, etc.) in infinite-dimensional spaces
saddle point theorem, deformation lemma, quasilinear equation, Abstract critical point theory (Morse theory, Lyusternik-Shnirel'man theory, etc.) in infinite-dimensional spaces
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 17 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Top 10% | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
