Results 31 to 40 of about 2,136 (139)
Rational curves and ruled orders on surfaces
Journal of Algebra, 2015 We study ruled orders. These arise naturally in the Mori program for orders on projective surfaces and morally speaking are orders on a ruled surface ramified on a bisection and possibly some fibres. We describe fibres of a ruled order and show they are in some sense rational.
Daniel Chan, Kenneth Chan
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Computation of symmetries of rational surfaces
<p>In this paper, we provided, first, a general symbolic algorithm for computing the symmetries of a given rational surface, based on the classical differential invariants of surfaces, i.e., Gauss curvature and mean curvature.
Hermoso, Carlos +4 more
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Affine rulings of normal rational surfaces
Osaka Journal of Mathematics, 2001 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Daigle, Daniel, Russell, Peter
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Zero-dimensional subschemes of ruled varieties
, 2004 In this paper we study zero-dimensional subschemes of ruled varieties, with a particular attention to the case of Hirzebruch surfaces and rational normal scrolls razionali.
Bocci, C. +11 more
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Singular locus of rational ruled surfaces
, 2002 In french, 25 pages. Many improvements in the proofs. New results included : the study of GIT properties of the morphism and the study of the singular locus of the image.
Perrin, Nicolas
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Pinwheels in symplectic rational and ruled surfaces and non‐squeezing of rational homology balls
We use almost toric fibrations and the symplectic rational blow‐up to determine when certain Lagrangian pinwheels, which we call liminal , embed in symplectic rational and ruled surfaces.
Johannes Hauber, Nikolas Adaloglou
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Implicitization of rational ruled surfaces with μ-bases
, 2009 J. Symbolic Comput. 44 (2009), 5, 479—489.International audienceChen, Sederberg, and Zheng introduced the notion of a µ-basis for a rational ruled surface in Chen et al. (2001) and showed that its resultant is the implicit equation of the surface, if the
Dohm, Marc
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Criteria for very ampleness of rank two vector bundles over ruled surfaces
, 2010 Very ampleness criteria for rank 2 vector bundles over smooth, ruled surfaces over rational and elliptic curves are given.
Alberto Alzati +3 more
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Rank-two vector bundles on non-minimal ruled surfaces [PDF]
, 2018 We continue previous work by various authors and study the birational geometry of moduli spaces of stable rank-two vector bundles on surfaces with Kodaira dimension $ -\infty $.
Aprodu, Marian +2 more
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Computing the symmetries of a ruled rational surface
, 2018 We present a method for computing all the symmetries of a rational ruled surface defined by a rational parametrization which works directly in parametric rational form, i.e. without computing or making use of the implicit equation of the surface. The method proceeds by translating the problem into the parameter space, and relies on polynomial system ...
Arribas, Alcázar +2 more
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