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arXiv · 1807.11133

Cr-invariants for surfaces in 4-space

Jorge Luiz Deolindo Silva
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Abstract

We establish cross-ratio invariants for surfaces in 4-space in an analogous way to Uribe-Vargas's work for surfaces in 3-space. We study the geometric locii of local and multi-local singularities of ortogonal projections of the surface. The cross-ratio invariants at $P_3(c)$-points are used to recover two moduli in the 4-jet of the projective parametrization of the surface and show the stable configurations of asymptotic curves.

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Jorge Luiz Deolindo Silva. 2018-07-30. Cr-invariants for surfaces in 4-space. https://arxiv.org/abs/1807.11133

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