The Poisson Bracket of Length functions in the Hitchin Component

Martin Bridgeman

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arXiv · 1502.05975

The Poisson Bracket of Length functions in the Hitchin Component

Martin Bridgeman

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Abstract

Wolpert's cosine formula on Teichm\"uller space gives the Weil-Petersson Poisson bracket $\{l_\alpha, l_\beta\}$ for geodesic length functions $l_\alpha,l_\beta$ of closed curves $\alpha,\beta$ as the sum of the cosines of the angle of intersection of the associated geodesics. This was recently generalized to Hitchin representations by Labourie. In this paper, we give a short proof of this generalization using Goldman's formula for the Poisson bracket on representation varieties of surface groups into reductive Lie groups.

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Martin Bridgeman. 2015-02-20. The Poisson Bracket of Length functions in the Hitchin Component. https://arxiv.org/abs/1502.05975

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