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arXiv · 1503.03198

A Quantum Gauss-Bonnet Theorem

Taylor Friesen
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Abstract

In their paper "Integrating curvature: From Umlaufsatz to J+ invariant" Lanzat and Polyak introduced a polynomial invariant of generic curves in the plane as a quantization of Hopf's Umlaufsatz, and showed that Arnold's J+ invariant could be derived from their polynomial, leading to an integral formula for J+. Here we extend their invariant to the case of homologically trivial generic curves in closed oriented surfaces with Riemannian metric. The resulting invariant turns out to be a quantization of a new formula for the rotation number, which can be viewed as a form of the Gauss-Bonnet Theorem. We show that J+ can be calculated from the generalized invariant when the Euler characteristic of the surface is nonzero, thereby obtaining an integral formula for J+ for homologically trivial curves in oriented surfaces with nonzero Euler characteristic.

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Taylor Friesen. 2015-03-11. A Quantum Gauss-Bonnet Theorem. https://arxiv.org/abs/1503.03198

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