The monodromy groups of Dolgachev's CY moduli spaces are Zariski dense☆
The monodromy groups of Dolgachev's CY moduli spaces are Zariski dense☆
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DOI:
10.1016/j.aim.2014.12.017
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发表时间:
2014-07
影响因子:
1.7
通讯作者:
Mao Sheng;Jinxing Xu;K. Zuo
中科院分区:
文献类型:
--
作者:
Mao Sheng;Jinxing Xu;K. Zuo
Abstract Let M n, 2 n+ 2 be the coarse moduli space of CY manifolds arising from a crepant resolution of double covers of P n branched along 2 n+ 2 hyperplanes in general position. We show that the monodromy group of a good family for M n, 2 n+ 2 is Zariski dense in the corresponding symplectic or orthogonal group if n≥ 3. In particular, the period map does not give a uniformization of any partial compactification of the coarse moduli space as a Shimura variety whenever n≥ 3. This disproves a conjecture of Dolgachev. As a consequence, the fundamental group of the coarse moduli space of m ordered points in P n is shown to be large once it is not a point. Similar Zariski-density result is obtained for moduli spaces of CY manifolds arising from cyclic covers of P n branched along m hyperplanes in general position. A classification towards the geometric realization problem of B. Gross for type A bounded symmetric domains is given.