Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Birational Geometry of symplectic resolutions of nilpotent orbits   In this paper, we shall prove that any two (projective) symplectic
resolutions of a nilpotent orbit closure in a classical simple Lie algebra are
connected by a finite sequence of diagrams which are locally trivial families
of Mukai flops of type A or of type D. A Mukai flop of type A is the same as a
stratified Mukai flop in our previous paper "Mukai flops and derived categories
II". On the other hand, a Mukai flop of type D comes from a nilpotent orbit in
so(2k). Let G^+ and G^- be two connected components of the orthogonal
Grassmannian G_{iso}(k,2k). Then the closure of this orbit has two Springer
resolutions via the cotanegent bundles T^*G^+ and T^*G^-, which is the Mukai
flop of type D. Our result would clarify the geometric meaning of the results
of Spaltenstein and Hesselink. To illustrate this, three examples will be
given. Another purpose of this paper is to give an affimative answer to a
conjecture in the paper "Uniqueness of crepant resolutions and symplectic
singularities" math.AG/0306091, for nilpotent orbit cases. A key idea is the
notion of a "Dixmier sheet" studied by Borho and Kraft.

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The categories of this paper are: nucl-ex
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The categories of this paper are: nlin
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The categories of this paper are: supr-con
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The categories of this paper are: eess
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The categories of this paper are: bayes-an
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The categories of this paper are: cmp-lg
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The categories of this paper are: astro-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: ao-sci
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The categories of this paper are: econ
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: cond-mat
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The categories of this paper are: chao-dyn