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Contact resolutions of projectivised nilpotent orbit closures

Baohua Fu
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Abstract

The projectivised nilpotent orbit closure P(\bar{O}) carries a natural contact structure on its smooth part. A resolution X \to P(\bar{O}) is called contact if the contact structure on P(O) extends to a contact structure on X. It turns out that contact resolutions, crepant resolutions and minimal models of P(\bar{O}) are all the same. In this note, we determine when the projectivised nilpotent orbit closure admits a contact resolution, and in the case of existence, we study the birational geometry among different contact resolutions.

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Baohua Fu. 2007-06-07. Contact resolutions of projectivised nilpotent orbit closures. https://arxiv.org/abs/math/0602088

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