Compactifications of rational maps, and the implicit equations of their images

In this paper, we give different compactifications for the domain and the codomain of an affine rational map f which parameterizes a hypersurface. We show that the closure of the image of this map (with possibly some other extra hypersurfaces) can be represented by a matrix of linear syzygies. We co...

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Detalles Bibliográficos
Autor: Botbol, Nicolas Santiago
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/16543
Acceso en línea:http://hdl.handle.net/11336/16543
Access Level:acceso abierto
Palabra clave:Rational Maps
Implicitization
Syzygies
https://purl.org/becyt/ford/1.1
https://purl.org/becyt/ford/1
Descripción
Sumario:In this paper, we give different compactifications for the domain and the codomain of an affine rational map f which parameterizes a hypersurface. We show that the closure of the image of this map (with possibly some other extra hypersurfaces) can be represented by a matrix of linear syzygies. We compactify A n−1 into an (n − 1)- dimensional projective arithmetically Cohen–Macaulay subscheme of some P N . One particular interesting compactification of A n−1 is the toric variety associated to the Newton polytope of the polynomials defining f . We consider two different compactifications for the codomain of f : P n and (P 1 ) n . In both cases we give sufficient conditions, in terms of the nature of the base locus of the map, for getting a matrix representation of its closed image, without involving extra hypersurfaces. This constitutes a direct generalization of the corresponding results established by Laurent Busé and Jean-Pierre Jouanolou (2003) [12], Laurent Busé et al. (2009) [9], Laurent Busé and Marc Dohm (2007) [11], Nicolás Botbol et al. (2009) [5] and Nicolás Botbol (2009).