Critical points of higher order for the normal map of immersions in R^ d
We study the critical points of the normal map ν : N M → R k + n , where M is an immersed k-dimensional submanifold of R k + n , N M is the normal bundle of M and ν ( m , u ) = m + u if u ∈ N m M. Usually, the image of these critical points is called the focal set. However, in that set there is a su...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2012 |
| País: | Brasil |
| Institución: | Universidade Federal de Viçosa (UFV) |
| Repositorio: | LOCUS Repositório Institucional da UFV |
| Idioma: | inglés |
| OAI Identifier: | oai:locus.ufv.br:123456789/21909 |
| Acceso en línea: | https://doi.org/10.1016/j.topol.2011.09.029 http://www.locus.ufv.br/handle/123456789/21909 |
| Access Level: | acceso abierto |
| Palabra clave: | Normal map Critical points Focal set Strong principal directions Veronese of curvature Ellipse of curvature |
| Sumario: | We study the critical points of the normal map ν : N M → R k + n , where M is an immersed k-dimensional submanifold of R k + n , N M is the normal bundle of M and ν ( m , u ) = m + u if u ∈ N m M. Usually, the image of these critical points is called the focal set. However, in that set there is a subset where the focusing is highest, as happens in the case of curves in R 3 with the curve of the centers of spheres with contact of third order with the curve. We give a definition of r-critical points of a smooth map between manifolds, and apply it to study the 2 and 3-critical points of the normal map in general and the 2-critical points for the case k = n = 2 in detail. In the later case we analyze the relation with the strong principal directions of Montaldi (1986) [2]. |
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