Discussiones Mathematicae Differential Inclusions 15(2) (1995) 129-148



Stanisław Migórski

Institute for Information Sciences, Jagellonian University
Nawojki 11, 30-072 Cracow, Poland


In this paper we study nonlinear evolution inclusions associated with second order equations defined on an evolution triple. We prove two existence theorems for the cases where the orientor field is convex valued and nonconvex valued, respectively. We show that when the orientor field is Lipschitzean, then the set of solutions of the nonconvex problem is dense in the set of solutions of the convexified problem.

Keywords: differential inclusion, relaxation, multifunction, gelfand triple, compact embedding.

1991 Mathematics Subject Classification: 34G20.


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