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arXiv · 1907.04465

Principal configurations around umbilics of spacelike surfaces in null hypersurfaces of $\mathbb{R}_1^4$

Matias Navarro·Oscar Palmas·Didier A. Solis
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Abstract

We study the principal configurations around an isolated $\eta$-umbilical point on a generic spacelike surface $S$ immersed in a null hypersurface $M$ of Minkowski space $\mathbb{R}_1^4$ relative to a well-defined null vector field $\eta$ orthogonal to the surface $S$. In the particular case of $M$ being a null rotation hypersurface of $\mathbb{R}_1^4$ we also recover the local Darbouxian principal configurations around that kind of $\eta$-umbilical points.

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Matias Navarro, Oscar Palmas, Didier A. Solis. 2019-07-10. Principal configurations around umbilics of spacelike surfaces in null hypersurfaces of $\mathbb{R}_1^4$. https://arxiv.org/abs/1907.04465

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