A cohomological characterization of Alexander schemes
A cohomological characterization of Alexander schemes
复制标题
亚历山大方案的上同调表征
DOI:
10.1007/s002220050336
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发表时间:
1999
影响因子:
3.1
通讯作者:
Shungen Kimura
中科院分区:
文献类型:
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作者:
Shungen Kimura
Vistoli defined Alexander schemes in [19], which behave like smooth varieties from the viewpoint of intersection theory with Q-coefficients. In this paper, we will affirmatively answer Vistoli’s conjecture that Alexander property is Zariski local. The main tool is the abelian category of bivariant sheaves, and we will spend most of our time for proving basic properties of this category. We show that a scheme is Alexander if and only if all the first cohomology groups of bivariant sheaves vanish, which is an analogy of Serre’s theorem, which says that a scheme is affine if and only if all the first cohomology groups of quasi-coherent sheaves vanish. Serre’s theorem implies that the union of affine closed subschemes is again affine. Mimicking the proof line by line, we will prove that the union of Alexander open subschemes is again Alexander.
DOI:
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发表时间:
2006
期刊:
II, Hiroshima Math.J. 35
影响因子:
--
作者:
Masayuki Hirokado;Hiroyuki Ito,Natsuo Saito;Masayuki Hirokado;Atsushi Shiho;Kazuhiro Fujiwara;Fumiharu Kato;中島 幸喜;Shun-ichi Kimura;Yukiyoshi Nakajima;Shunichi Kimura
通讯作者:
Shunichi Kimura