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Monotone preimages of dendrites - MaRDI portal

Monotone preimages of dendrites (Q1005157)

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scientific article; zbMATH DE number 5526265
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Monotone preimages of dendrites
scientific article; zbMATH DE number 5526265

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    Monotone preimages of dendrites (English)
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    6 March 2009
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    In 1991, J. J. Charatonik and K. Omiljanowski proved the following result: ``Let \(Y\) be a dendrite such that (1) all ramification points of \(Y\) are of order three; (2) the set \(R(X)\) is discrete. If a dendrite \(X\) can be mapped onto \(Y\) by a monotone mapping, then \(X\) contains a homeomorphic copy of \(Y\).'' In this paper the author gives a counterexample to this result, and provides an alternative proof for a characterization of dendrites monotonely equivalent to a universal dendrite that was originally proved using the erroneous result. Finally, in response to a question by J. J. Charatonik, it is shown that a dendrite contained in all of its monotone preimages must have a discrete set of ramification points.
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    dendrite
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    monotone map
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    monotone equivalence
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