Journal of Applied Mathematics and Stochastic Analysis 
Volume 13 (2000), Issue 1, Pages 51-72
doi:10.1155/S104895330000006X

On the structure of the solution set of evolution inclusions with Fréchet subdifferentials

Tiziana Cardinali

Perugia University, Department of Mathematics, Via Vanvitelli 1, Perugia 06123, Italy

Received 1 May 1998; Revised 1 November 1999

Abstract

In this paper we consider a Cauchy problem in which is present an evolution inclusion driven by the Fréchet subdifferential o f of a function f:ΩR{+} (Ω is an open subset of a real separable Hilbert space) having a φ-monotone . subdifferential of order two and a perturbation F:I×ΩPfc(H) with nonempty, closed and convex values.

First we show that the Cauchy problem has a nonempty solution set which is an Rδ-set in C(I,H), in particular, compact and acyclic. Moreover, we obtain a Kneser-type theorem. In addition, we establish a continuity result about the solution-multifunction xS(x). We also produce a continuous selector for the multifunction xS(x). As an application of this result, we obtain the existence of solutions for a periodic problem.