Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The geometry of weakly selfdual Kahler surfaces   We study Kahler surfaces with harmonic anti-selfdual Weyl tensor. We provide
an explicit local description, which we use to obtain the complete
classification in the compact case. We give new examples of extremal Kahler
metrics, including Kahler-Einstein metrics and conformally Einstein Kahler
metrics. We also extend some of our results to almost Kahler 4-manifolds,
providing new examples of Ricci-flat almost Kahler metrics which are not
Kahler.

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The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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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: nlin
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The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-th