Polygon Spaces and Grassmannians
نویسنده
چکیده
We study the moduli spaces of polygons in R and R, identifying them with subquotients of 2-Grassmannians using a symplectic version of the Gelfand-MacPherson correspondence. We show that the bending flows defined by Kapovich-Millson arise as a reduction of the Gelfand-Cetlin system on the Grassmannian, and with these determine the pentagon and hexagon spaces up to equivariant symplectomorphism. Other than invocation of Delzant’s theorem, our proofs are purely polygon-theoretic in nature.
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تاریخ انتشار 1995