Results 21 to 30 of about 2,136 (139)
On the Singularities of Surfaces Ruled by Conics [PDF]
, 2014 We classify the singularities of a surface ruled by conics: they are rational double points of type A n or D n . This is proved by showing that they arise from a precise series of blow-ups of a suitable surface geometrically ruled by conics. We determine
BRUNDU, MICHELA, SACCHIERO, GIANNI
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A computational study of ruled surfaces [PDF]
, 2009 International audienceWe study rational ruled surfaces and $\mu$-bases which were recently considered in a series of articles by Chen and coworkers. We give short and conceptual proofs with geometric insights and efficient algorithms.
Busé, Laurent +2 more
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Rational ruled surfaces as symplectic hyperplane sections
Transactions of the American Mathematical Society, 2023 We study embeddability of rational ruled surfaces as symplectic hyperplane sections into closed integral symplectic manifolds. From this we obtain results on Stein fillability of Boothby–Wang bundles over rational ruled surfaces.
Kwon, Myeonggi, Oba, Takahiro
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The Atiyah–Jones conjecture for rational surfaces [PDF]
, 2008 We show that if the Atiyah–Jones conjecture holds for a surface X, then it also holds for the blow-up of X at a point. Since the conjecture is known to hold for P2 and for ruled surfaces, it follows that the conjecture is true for all rational ...
Gasparim, Elizabeth
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General position of points on a rational ruled surface [PDF]
Beiträge zur Algebra und Geometrie / Contributions to Algebra and Geometry, 2017 There are several different definitions for the notion of points in general position in \(\mathbb{P}^2\), some of which, due to the authors, are finalized to very ampleness criteria for rank 2 vector bundles [\textit{A. Alzati} and \textit{A. Tortora}, Rev. Mat. Complut. 28, No. 3, 623--654 (2015; Zbl 1330.14070)].
A. ALZATI, A. Tortora
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Topology of symplectomorphism groups of rational ruled surfaces [PDF]
Journal of the American Mathematical Society, 2000 Let M M be either
Abreu, Miguel, McDuff, Dusa
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Real rational conchoids of curves and surfaces [PDF]
, 2013 Diese Arbeit beschäftigt sich mit der Konstruktion von Konchoiden und deren Eigenschaften in der Euklidischen Ebene und im Euklidischen Raum.Die Konstruktion kann relativ grob, wie folgt beschrieben werden: Von einer gegebenen Kurve wird eine ...
Gruber, David
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An explicit construction of ruled surfaces [PDF]
, 2009 The main goal of this paper is to give a general algorithm to compute, via computer-algebra systems, an explicit set of generators of the ideals of the projective embeddings of ruled surfaces, i.e. projectivizations of rank two vector bundles over curves,
Alzati, Alberto +3 more
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On rational and ruled double planes
, 2002 Following the ideas of Castelnuovo and Enriques, we classify the birational equivalence classes of double planes which are rational or ruled surfaces. In order to do this, we prove that the vanishing of the m-adjoint linear system to the branch curve of ...
CALABRI, Alberto
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Normal projective degenerations of rational and ruled surfaces.
Journal für die reine und angewandte Mathematik (Crelles Journal), 1986 Let \(f: X\to T\) be a projective flat morphism from a normal threefold X to a smooth affine curve T over the field of complex numbers. Suppose that \(X_ t\) is a smooth surface for \(t\neq 0\) and \(X_ 0\) is a normal surface, where \(0\in T\) is a distinguishd point. Then \(X_ 0\) is a called a normal projective degeneration of \(X_ t\).
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