Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Complex structure on the rational blowdown of sections in E(4)   We show that there is a complex structure on the symplectic 4-manifold $W_{4,
k}$ obtained from the elliptic surface E(4) by rationally blowing down $k$
sections for $2\le k\le 9$. And we interpret it via ${\mathbb Q}$-Gorenstein
smoothing. This answers affirmatively to a question raised by R. Gompf.

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The categories of this paper are: math-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
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The categories of this paper are: supr-con
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The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
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The categories of this paper are: adap-org
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The categories of this paper are: physics
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The categories of this paper are: chao-dyn
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The categories of this paper are: stat
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The categories of this paper are: cond-mat
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The categories of this paper are: solv-int
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The categories of this paper are: cmp-lg