Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Self-duality of the compactified Ruijsenaars-Schneider system from
  quasi-Hamiltonian reduction   The Delzant theorem of symplectic topology is used to derive the completely
integrable compactified Ruijsenaars-Schneider III(b) system from a
quasi-Hamiltonian reduction of the internally fused double SU(n) x SU(n). In
particular, the reduced spectral functions depending respectively on the first
and second SU(n) factor of the double engender two toric moment maps on the
III(b) phase space CP(n-1) that play the roles of action-variables and
particle-positions. A suitable central extension of the SL(2,Z) mapping class
group of the torus with one boundary component is shown to act on the
quasi-Hamiltonian double by automorphisms and, upon reduction, the standard
generator S of the mapping class group is proved to descend to the Ruijsenaars
self-duality symplectomorphism that exchanges the toric moment maps. We give
also two new presentations of this duality map: one as the composition of two
Delzant symplectomorphisms and the other as the composition of three Dehn twist
symplectomorphisms realized by Goldman twist flows. Through the well-known
relation between quasi-Hamiltonian manifolds and moduli spaces, our results
rigorously establish the validity of the interpretation [going back to Gorsky
and Nekrasov] of the III(b) system in terms of flat SU(n) connections on the
one-holed torus.

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The categories of this paper are: adap-org
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The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-th
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The categories of this paper are: physics
34
The categories of this paper are: chem-ph
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The categories of this paper are: eess
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The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: hep-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph