首页 | 本学科首页   官方微博 | 高级检索  
     


On sums of Darboux and nowhere constant continuous functions
Authors:Krzysztof Ciesielski   Janusz Pawlikowski
Affiliation:Department of Mathematics, West Virginia University, Morgantown, West Virginia 26506-6310 ; Department of Mathematics, University of Wroclaw, pl. Grunwaldzki 2/4, 50-384 Wroclaw, Poland -- and --Department of Mathematics, West Virginia University, Morgantown, West Virginia 26506-6310
Abstract:We show that the property
(P)
for every Darboux function $gcolon{mathbb R}tomathbb{R} $ there exists a continuous nowhere constant function $fcolon{mathbb R}tomathbb{R} $ such that $f+g$ is Darboux
follows from the following two propositions:
(A)
for every subset $S$ of $mathbb{R} $ of cardinality $mathfrak{c}$ there exists a uniformly continuous function $fcolonmathbb{R}to[0,1]$ such that $f[S]=[0,1]$,
(B)
for an arbitrary function $hcolonmathbb{R}tomathbb{R} $ whose image $h[mathbb{R} ]$ contains a non-trivial interval there exists an $Asubsetmathbb{R} $ of cardinality $mathfrak{c}$ such that the restriction $hrestriction A$ of $h$ to $A$is uniformly continuous,
which hold in the iterated perfect set model.

Keywords:Darboux   nowhere constant   images of continuous functions
点击此处可从《Proceedings of the American Mathematical Society》浏览原始摘要信息
点击此处可从《Proceedings of the American Mathematical Society》下载全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号