On a sharp bound for the regularity index of any set of fat points
โ Scribed by Giuliana Fatabbi; Anna Lorenzini
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 178 KB
- Volume
- 161
- Category
- Article
- ISSN
- 0022-4049
No coin nor oath required. For personal study only.
โฆ Synopsis
We propose an upper bound for the regularity index of fat points of P n with no geometric conditions on the points. Whenever the conjecture is true, the bound is sharp. It is, in fact, reached when there are points with high multiplicities either on a line or on some rational curve. Besides giving an easy proof of the conjecture in P 2 , we prove it in P 3 , by using some preliminary results which hold, more generally, in P n .
๐ SIMILAR VOLUMES
Let X be the surface obtained by blowing up general points p 1 p n of the projective plane over an algebraically closed ground field k, and let L be the pullback to X of a line on the plane. If C is a rational curve on X with C โข L = d, then for every t there is a natural map C C t โ X X L โ C C t +
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