The geometry of the flex locus of a hypersurface

We give a formula in terms of multidimensional resultants for an equation for the flex locus of a projective hypersurface, generalizing a classical result of Salmon for surfaces in $\mathbb{P}^{3}$. Using this formula, we compute the dimension of this flex locus, and an upper bound for the degree of...

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Detalles Bibliográficos
Autores: Busé, Laurent, D'Andrea, Carlos, 1973-, Sombra, Martín, Weimann, Martin
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/168517
Acceso en línea:https://hdl.handle.net/2445/168517
Access Level:acceso abierto
Palabra clave:Hipersuperfícies
Geometria algebraica
Àlgebra commutativa
Hypersurfaces
Algebraic geometry
Commutative algebra
Descripción
Sumario:We give a formula in terms of multidimensional resultants for an equation for the flex locus of a projective hypersurface, generalizing a classical result of Salmon for surfaces in $\mathbb{P}^{3}$. Using this formula, we compute the dimension of this flex locus, and an upper bound for the degree of its defining equations. We also show that, when the hypersurface is generic, this bound is reached, and that the generic flex line is unique and has the expected order of contact with the hypersurface.