Special Session 96: Evolutionary Equations Systems

Impulsive and Dirichlet problems driven by second order differential inclusions.
Giulia Duricchi
Universita` degli Studi di Firenze
Italy
Co-Author(s):    Tiziana Cardinali
Abstract:
In recent joint papers with Tiziana Cardinali we investigate in Banach spaces the existence of impulsive mild solutions for a problem driven by the following semilinear second order differential inclusion $\begin{equation*} x''(t) \in Ax(t)+F(t,x(t),x'(t)),\ \text{a.e.}\ t \in [0,\infty) \setminus \lbrace t_k \rbrace_k \end{equation*}$ and the existence of strong solutions for a Dirichlet problem governed by the following Duffing differential inclusion $\begin{equation*} -x''(t)-r(t)x(t) \in F(t,x(t)),\ t \in [0,a] \end{equation*}$ To establish the first goal, we show the existence of mild solutions on a bounded interval. Then, by using a glueing method, we achieve the existence of impulsive mild solutions on $[0,\infty)$. While to study the Duffing Dirichlet problem, we apply a fixed point result to an appropriate solution operator. All results are proved without strong compactness assumptions. Finally, thanks to these findings, the controllability for problems driven by ordinary/partial differential equations is obtained.