On Nagata’s Conjecture
نویسنده
چکیده
This paper gives an improved lower bound on the degrees d such that for general points p1, . . . , pn ∈ P 2 and m > 0 there is a plane curve of degree d vanishing at each pi with multiplicity at least m.
منابع مشابه
Variations on Nagata’s Conjecture
Here we discuss some variations of Nagata’s conjecture on linear systems of plane curves. The most relevant concerns non-effectivity (hence nefness) of certain rays, which we call good rays, in the Mori cone of the blowup Xn of the plane at n ≥ 10 general points. Nagata’s original result was the existence of a good ray for Xn with n ≥ 16 a square number. Using degenerations, we give examples of...
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تاریخ انتشار 2008