Ruled surfaces whose flecnode curves have plane branches
نویسندگان
چکیده
منابع مشابه
Rational curves and ruled orders on surfaces
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. We also determine the Hilbert scheme of rational curves and hence the corresponding non-commutative Mori contraction. T...
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We study the structure of collections of algebraic curves in three dimensions that have many curve-curve incidences. In particular, let k be a field and let L be a collection of n space curves in k, with n << (char(k)) or char(k) = 0. Then either A) there are at most O(n) points in k hit by at least two curves, or B) at least Ω(n) curves from L must lie on a bounded-degree surface, and many of ...
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In this paper we study the geometry of the Severi varieties parametrizing curves on the rational ruled surface Fn. We compute the number of such curves through the appropriate number of fixed general points on Fn (Theorem 1.1), and the number of such curves which are irreducible (Theorem 1.3). These numbers are known as Severi degrees; they are the degrees of unions of components of the Hilbert...
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Article history: Received 10 November 2007 Received in revised form 11 June 2008 Accepted 14 September 2008 Available online 23 September 2008
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1915
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-1915-1501026-9