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Symplectic automorphisms of CP^2 and the Thompson group T

Alexandr Usnich
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Abstract

We explain how to construct a morphism from the group of birational automorphisms of CP^2 preserving the logarithmic Poisson bracket to the Thompson group T. Than we give a linear representation of the former group, provide some information about Thompson group T and give it's new presentation in terms of generators and relations, and speculate about the presentation of the group of birational symplectomorphisms.

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Alexandr Usnich. 2006-12-19. Symplectic automorphisms of CP^2 and the Thompson group T. https://arxiv.org/abs/math/0611604

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