Conformal geometry, Euler numbers, and global invertibility in higher dimensions

Frederico Xavier

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arXiv · 2002.12884

Conformal geometry, Euler numbers, and global invertibility in higher dimensions

Frederico Xavier

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Abstract

It is shown that in dimension at least three a local diffeomorphism of Euclidean n-space into itself is injective provided that the pull-back of every plane is a Riemannian submanifold which is conformal to a plane. Using a similar technique one recovers the result that a polynomial local biholomorphism of complex $n$-space into itself is invertible if and only if the pull-back of every complex line is a connected rational curve. These results are special cases of our main theorem, whose proof uses geometry, complex analysis, elliptic partial differential equations, and topology.

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Frederico Xavier. 2020-02-28. Conformal geometry, Euler numbers, and global invertibility in higher dimensions. https://arxiv.org/abs/2002.12884

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