Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Moving frames on the twistor space of self-dual positive Einstein
  4-manifolds   The twistor space of self-dual positive Einstein manifolds naturally admits
two 1-parameter families of Riemannian metrics, one is the family of canonical
deformation metrics and the other is the family introduced by B. Chow and D.
Yang in 1989. The purpose of this paper is to compare these two families. In
particular we compare the Ricci tensor and the behavior under the Ricci flow of
these families. As an application, we propose a new proof to the fact that a
locally irreducible self-dual positive Einstein 4-manifold is isometric to
either $S^4$ with a standard metric or $\PP^2(\C)$ with a Fubini-Study metric.

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The categories of this paper are: physics
21
The categories of this paper are: adap-org
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The categories of this paper are: plasm-ph
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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: comp-gas
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The categories of this paper are: gr-qc
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The categories of this paper are: quant-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
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The categories of this paper are: hep-lat
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The categories of this paper are: astro-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: nlin