Cardinal coefficients related to surjectivity, Darboux, and Sierpiński-Zygmund maps
نویسندگان
چکیده
منابع مشابه
Approximate Maps Characterizing Injectivity and Surjectivity of Maps
In the theory of inverse systems, in order to study the properties of a space X or a map f : X → Y between spaces, one expands X to an inverse system X or expands f to a map f : X → Y between the inverse systems, and then work on X or f . In this paper, we define approximate injectivity (resp., surjectivity) for approximate maps, and show that a map f : X → Y between compact metric spaces is in...
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(1 + cX(t, z))τ Department of Mathematics, Brandeis University, Waltham, Mass 02254, USA. The support of a National Science Foundation grant # DMS-9503246 is gratefully acknowledged. Université de Louvain, 1348 Louvain-la-Neuve, Belgium and Department of Mathematics, Brandeis University, Waltham, Mass 02254, USA. The support of a National Science Foundation grant # DMS-9503246, a Nato, a FNRS a...
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In this paper we show that if the real line R is not a union of less than continuum many of its meager subsets then there exists an almost continuous Sierpiński–Zygmund function having a perfect road at each point. We also prove that it is consistent with ZFC that every Darboux function f :R→ R is continuous on some set of cardinality continuum. In particular, both these results imply that the ...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2016
ISSN: 0002-9939,1088-6826
DOI: 10.1090/proc/13294