ArticleOriginal scientific text

Title

Selections and representations of multifunctions in paracompact spaces

Authors 1, 1

Affiliations

  1. S.I.S.S.A., Via Beirut 4, 34014 Trieste, Italy.

Abstract

Let (X,T) be a paracompact space, Y a complete metric space, F:X2Y a lower semicontinuous multifunction with nonempty closed values. We prove that if T+ is a (stronger than T) topology on X satisfying a compatibility property, then F admits a T+-continuous selection. If Y is separable, then there exists a sequence (fn) of T+-continuous selections such that F(x)={fn(x);n1}¯ for all x ∈ X. Given a Banach space E, the above result is then used to construct directionally continuous selections on arbitrary subsets of ℝ × E.

Keywords

directionally continuous selections

Bibliography

  1. J. P. Aubin and A. Cellina, Differential Inclusions, Springer, Berlin 1984.
  2. A. Bressan,HAMUpper and lower semicontinuous differential inclusions. A unified approach, in: Controllability and Optimal Control, H. Sussmann (ed.), M. Dekker, New York 1989, 21-32.
  3. A. Bressan and G. Colombo, Boundary value problems for lower semicontinuous differential inclusions, Funkcial. Ekvac., to appear.
  4. A. Bressan and A. Cortesi, Directionally continuous selections in Banach spaces, Nonlin. Anal. 13 (1989), 987-992.
  5. E. Michael, Selected selection theorems, Amer. Math. Monthly 63 (1956), 233-238.
  6. E. Michael, Continuous selections. I, Ann. of Math. 63 (1956), 361-382.
Pages:
209-216
Main language of publication
English
Received
1991-02-07
Published
1992
Exact and natural sciences