Modified continuity and a generalisation of Michael's selection theorem

Set-Valued Analysis - Tập 1 - Trang 365-378 - 1993
J. R. Giles1, M. O. Bartlett1
1Department of Mathematics, University of Newcastle, Australia

Tóm tắt

We modify the definitions of continuity and lower semicontinuity for single-valued mappings and upper and lower semicontinuity for set-valued mappings. For single-valued mappings we have a generalisation of Osgood's theorem and for set-valued mappings we have an extension of Fort's theorem and a generalisation of Michael's selection theorem producing a densely defined selection with a natural continuity property relative to the domain.

Tài liệu tham khảo

Borwein, J, Fitzpatrick, S. and Kenderov, P., Minimal convex uscos and monotone operators on small sets,Canad. J. Math. 43 (1991), 461–476. Coban, M.M., Kenderov, P.S. and Revalski, J.P., Densely defined selections of multivalued mappings,Trans. Amer. Math. Soc. (to appear). Kenderov, P.S. and Giles, J.R., On the structure of Banach spaces with Maxur's intersection property,Math. Ann. 291 (1991), 463–473. Kelly, J.L. and Namioka, I.,Linear Topological Spaces, Van Nostrand, New York, 1963. Kenderov, P.S., Continuity-like properties of set-valued mappings,Serdica Bulg. Math. Publ. 9 (1983), 149–160. Michael, E., Selected selection theorems,Amer. Math. Monthly 63 (1956), 233–238.