Solvability of a forced autonomous Duffing's equation with periodic boundary conditions in the presence of damping

Gupta, Chaitan P.

Applications of Mathematics, Tome 38 (1993) no. 3, pp. 195-203

Résumé

Let $g$: $\bold R\rightarrow \bold R$ be a continuous function, $e$: $[0,1]\rightarrow \bold R$ a function in $L^2[0,1]$ and let $c \in \bold R$, $c\neq 0$ be given. It is proved that Duffing's equation $u'' + cu' + g(u)=e(x)$, $0$, $u(0)=u(1)$, $u'(0)=u'(1)$ in the presence of the damping term has at least one solution provided there exists an $\bold R > 0$ such that $g(u)u\geq 0$ for $|u|\geq \bold R$ and $\int^{1}_{0}e(x)dx=0$. It is further proved that if $g$ is strictly increasing on $\bold R$ with $\lim_{u\rightarrow -\infty} g(u)=-\infty$, $\lim_{u\rightarrow \infty} g(u)=\infty$ and it Lipschitz continuous with Lipschitz constant $\alpha4\pi^2+c^2$, then Duffing's equation given above has exactly one solution for every $e\in L^2[0,1]$.

Détail

DOI : 10.21136/AM.1993.104546

Classification : 34B15, 34C25, 47H15, 47J05, 47N20
Keywords: Dufiing's equation; damping; forced autonomous Duffing’s equation; Leray-Schauder continuation theorem; Wirtinger type inequalities; uniqueness; boundary value problem