Dissecting the 2-sphere by immersions
نویسنده
چکیده
The self intersection of an immersion i : S2 → R3 dissects S2 into pieces which are planar surfaces (unless i is an embedding). In this work we determine what collections of planar surfaces may be obtained in this way. In particular, for every n we construct an immersion i: S2 → R3 with 2n triple points, for which all pieces are discs. Keyword Immersions of the 2-sphere Mathematics Subject Classification (2000) 57M99 · 57R42
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