摘要翻译:
经典地知道,实射影3空间中的实三次曲面不能有一个以上的孤立点(局部由x^2+y^2+z^2=0),而最多可以有四个结点(x^2+y^2-z^2=0)。证明了在实射影3-空间中任意次为3的曲面上,孤立点的最大可能个数严格小于结点的最大可能个数。相反地,我们利用Brusotti定理的一个精化版本,利用Chmutov的一个构造来获得含有多个孤立点的曲面。最后,我们将这种构造应用于所有$k\ge1$的实代数曲面中,得到了具有$a_{2k-1}^\smbullet$类型奇异点的实代数曲面。
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英文标题:
《Surfaces with Many Solitary Points》
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作者:
Erwan Brugalle Oliver Labs
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最新提交年份:
2008
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分类信息:
一级分类:Mathematics 数学
二级分类:Algebraic Geometry 代数几何
分类描述:Algebraic varieties, stacks, sheaves, schemes, moduli spaces, complex geometry, quantum cohomology
代数簇,叠,束,格式,模空间,复几何,量子上同调
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英文摘要:
It is classically known that a real cubic surface in the real projective 3-space cannot have more than one solitary point (locally given by x^2+y^2+z^2=0) whereas it can have up to four nodes (x^2+y^2-z^2=0). We show that on any surface of degree at least 3 in the real projective 3-space, the maximum possible number of solitary points is strictly smaller than the maximum possible number of nodes. Conversely, we adapt a construction of Chmutov to obtain surfaces with many solitary points by using a refined version of Brusotti's theorem. Finally, we adapt this construction to get real algebraic surfaces with many singular points of type $A_{2k-1}^\smbullet$ for all $k\ge 1$.
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PDF链接:
https://arxiv.org/pdf/0801.4283