Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analytic rigidity of K-trivial extremal contractions of smooth 3-folds   We discuss the problem of classifying birational extremal contractions of
smooth threefolds where the canonical bundle is trivial along the curves
contracted, in the case when a divisor is contracted to a point. We prove the
analytic rigidity of the contraction in the case this divisor is normal of
degree >= 5 (i.e. we show that the analytic structure of the contraction is
completely determined by the isomorphism class of the exceptional locus and its
normal bundle in X). This was previously known only in the case of smooth
exceptional locus.

19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
18
The categories of this paper are: econ
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The categories of this paper are: acc-phys
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
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The categories of this paper are: solv-int
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The categories of this paper are: cond-mat
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The categories of this paper are: astro-ph