Dense Continuity and Selections of Set-Valued Mappings
Serdica Mathematical Journal, Tome 24 (1998) no. 1, pp. 49-72
Cet article a éte moissonné depuis la source Bulgarian Digital Mathematics Library
A theorem proved by Fort in 1951 says that an upper or lower
semi-continuous set-valued mapping from a Baire space A into non-empty
compact subsets of a metric space is both lower and upper semi-continuous
at the points of a dense Gδ -subset of A.
In this paper we show that the conclusion of Fort’s theorem holds under
the weaker hypothesis of either upper or lower quasi-continuity. The
existence of densely defined continuous selections for lower quasi-continuous
mappings is also proved.
Keywords:
Set-Valued Mappings, Selections, Semi-Continuity, Quasi-Continuity, Generic, Baire Category
@article{SMJ2_1998_24_1_a6,
author = {Kenderov, Petar and Moors, Warren and Revalski, Julian},
title = {Dense {Continuity} and {Selections} of {Set-Valued} {Mappings}},
journal = {Serdica Mathematical Journal},
pages = {49--72},
year = {1998},
volume = {24},
number = {1},
language = {en},
url = {http://geodesic.mathdoc.fr/item/SMJ2_1998_24_1_a6/}
}
Kenderov, Petar; Moors, Warren; Revalski, Julian. Dense Continuity and Selections of Set-Valued Mappings. Serdica Mathematical Journal, Tome 24 (1998) no. 1, pp. 49-72. http://geodesic.mathdoc.fr/item/SMJ2_1998_24_1_a6/