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Obstructions to deforming curves on a  -fold, I: A generalization of Mumford's example and an application to  schemes
Author(s):
Shigeru
Mukai;
Hirokazu
Nasu
Journal:
J. Algebraic Geom.
18
(2009),
691-709.
Posted:
August 14, 2008
MathSciNet review:
2524595
Retrieve article in:
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Abstract |
References |
Additional information
Abstract:
We give a sufficient condition for a first order infinitesimal deformation of a curve on a  -fold to be obstructed. As application we construct generically non-reduced components of the Hilbert schemes of uniruled  -folds and the Hom scheme from a general curve of genus five to a general cubic  -fold.
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Additional Information:
Shigeru
Mukai
Affiliation:
Research Institute for Mathematical Sciences, Kyoto University, Kyoto 606-8502, Japan
Email:
mukai@kurims.kyoto-u.ac.jp
Hirokazu
Nasu
Affiliation:
Research Institute for Mathematical Sciences, Kyoto University, Kyoto 606-8502, Japan
Email:
nasu@kurims.kyoto-u.ac.jp
PII:
S 1056-3911(08)00502-X
Received by editor(s):
May 23, 2007
Received by editor(s) in revised form:
September 28, 2007
Posted:
August 14, 2008
Additional Notes:
During this research, the first author was supported in part by the JSPS Grant-in-Aid for Scientific Research (B) 17340006. The second author was supported in part by the 21st century COE program ``Formation of an International Center of Excellence in the Frontier of Mathematics and Fostering of Researchers in Future Generations''.
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