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arXiv · 1004.4311

The Pentagram Integrals on Inscribed Polygons

Richard Evan Schwartz·Serge Tabachnikov
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Abstract

The pentagram map is a natural iteration on projective equivalence classes of (twisted) n-gons in the projective plane. It was recently proved ([OST]) that the pentagram map is completely integrable, with the complete set of Poisson commuting integrals given by the polynomials O1,...,O[n/2],On and E1,...,E[n/2],En, previously constructed in [S3]. These polynomials are somewhat reminiscent of the symmetric polynomials. It was observed in computer experiments that if a polygon is inscribed into a conic then Oi=Ei for all i. The goal of the paper is to prove this theorem. The proof is combinatorial, and it was also suggested by computer experimentation.

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BibTeXRIS

Richard Evan Schwartz, Serge Tabachnikov. 2010-04-24. The Pentagram Integrals on Inscribed Polygons. https://arxiv.org/abs/1004.4311

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