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arXiv · 1204.0420

Curved noncommutative torus and Gauss--Bonnet

Ludwik Dabrowski·Andrzej Sitarz
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Abstract

We study perturbations of the flat geometry of the noncommutative two-dimensional torus T^2_θ(with irrational θ). They are described by spectral triples (A_θ, \H, D), with the Dirac operator D, which is a differential operator with coefficients in the commutant of the (smooth) algebra A_θof T_θ. We show, up to the second order in perturbation, that the zeta-function at 0 vanishes and so the Gauss-Bonnet theorem holds. We also calculate first two terms of the perturbative expansion of the corresponding local scalar curvature.

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Ludwik Dabrowski, Andrzej Sitarz. 2012-04-02. Curved noncommutative torus and Gauss--Bonnet. https://doi.org/10.1063/1.4776202

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