arXiv math/98030511998-03-12math.DGhep-thmath.FA

Twisted higher index theory on good orbifolds and fractional quantum numbers

Matilde Marcolli, Varghese Mathai

备注：: 47 pages, Latex

英文摘要：

The twisted Connes-Moscovici higher index theorem is generalized to the case of good orbifolds. The higher index is shown to be a rational number, and in fact non-integer in specific examples of 2-orbifolds. This results in a non-commutative geometry model that predicts the occurrence of fractional quantum numbers in the Hall effect on the hyperbolic plane.

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