Smooth quasiregular mappings with branching
Publications Mathématiques de l'IHÉS, Volume 100 (2004), p. 153-170

We give an example of a 𝒞 3-ϵ -smooth quasiregular mapping in 3-space with nonempty branch set. Moreover, we show that the branch set of an arbitrary quasiregular mapping in n-space has Hausdorff dimension quantitatively bounded away from n. By using the second result, we establish a new, qualitatively sharp relation between smoothness and branching.

@article{PMIHES_2004__100__153_0,
     author = {Bonk, Mario and Heinonen, Juha},
     title = {Smooth quasiregular mappings with branching},
     journal = {Publications Math\'ematiques de l'IH\'ES},
     publisher = {Springer},
     volume = {100},
     year = {2004},
     pages = {153-170},
     doi = {10.1007/s10240-004-0024-8},
     zbl = {1063.30021},
     mrnumber = {2102699},
     language = {en},
     url = {http://www.numdam.org/item/PMIHES_2004__100__153_0}
}
Bonk, Mario; Heinonen, Juha. Smooth quasiregular mappings with branching. Publications Mathématiques de l'IHÉS, Volume 100 (2004) pp. 153-170. doi : 10.1007/s10240-004-0024-8. http://www.numdam.org/item/PMIHES_2004__100__153_0/

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