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Mappings of finite distortion: Size of the branch set

  • Chang-Yu Guo , Stanislav Hencl and Ville Tengvall ORCID logo EMAIL logo

Abstract

We study the branch set of a mapping between subsets of n, i.e., the set where a given mapping is not defining a local homeomorphism. We construct several sharp examples showing that the branch set or its image can have positive measure.

MSC 2010: 30C65; 26B10

Communicated by Juha Kinnunen


Award Identifier / Grant number: 277923

Award Identifier / Grant number: 153599

Award Identifier / Grant number: 165848

Funding statement: Chang-Yu Guo was supported by Swiss National Science Foundation Grant 153599 and 165848. Stanislav Hencl and Ville Tengvall were supported by the ERC CZ grant LL1203 of the Czech Ministry of Education. Ville Tengvall was also supported by the Academy of Finland Project 277923.

Acknowledgements

The authors want to express their gratitude to Kai Rajala, Aapo Kauranen and Pawel Goldstein for their valuable comments. The authors would also like to thank the anonymous referees for their very helpful comments that greatly improved the readability of the manuscript.

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Received: 2017-06-26
Revised: 2018-03-15
Accepted: 2018-03-16
Published Online: 2018-03-30
Published in Print: 2020-10-01

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