Article
Keywords:
nonuniqueness; time-periodical solutions; semilinear equation; irrational periods; dual variational method
Summary:
The author examined non-zero $T$-periodic (in time) solutions for a semilinear beam equation under the condition that the period $T$ is an irrational multiple of the length. It is shown that for a.e. $T \in R^1$ (in the sense of the Lebesgue measure on $R^1$) the solutions do exist provided the right-hand side of the equation is sublinear.
References:
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MR 0289918