Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Multiplicity-free Hamiltonian actions need not be K\"ahler   We show that Tolman's example (of a six dimensional Hamiltonian $T^2$-space
with isolated fixed points and no compatible K\"{a}hler structure) can be
constructed from the flag variety $U(3)/U(1)^3$ by $U(2)$-equivariant
symplectic surgery. This implies that Tolman's space has a ``transversal
multiplicity-free'' action of $U(2)$ and that Delzant's theorem ``every compact
multiplicity-free torus action is K\"{a}hler'' \cite{D1} does not generalize to
non-abelian actions.

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The categories of this paper are: gr-qc
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The categories of this paper are: ao-sci
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The categories of this paper are: astro-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: physics
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The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
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The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: plasm-ph
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The categories of this paper are: stat
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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: hep-lat
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The categories of this paper are: mtrl-th