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Limit sets as examples in noncommutative geometry

John Lott
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Abstract

The fundamental group of a hyperbolic manifold acts on the limit set, giving rise to a cross-product C^* algebra. We construct nontrivial K-cycles for the cross-product algebra, thereby extending some results of Connes and Sullivan to higher dimensions. We also show how the Patterson-Sullivan measure on the limit set can be interpreted as a center-valued KMS state.

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John Lott. 2005-03-25. Limit sets as examples in noncommutative geometry. https://arxiv.org/abs/math/0404346

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