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arXiv · 1301.2647

Poincaré series and rational cohomology rings of Kac-Moody groups and their flag manifolds

Zhao Xu-an·Jin Chunhua·Zhang Jimin
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Abstract

In this paper, we study the rational cohomology rings of indefinite Kac-Moody groups and their flag manifolds. By extracting the information of cohomology from the Poincaré series, we are able to determine the rational cohomology rings of Kac-Moody groups and their flag manifolds. Since Kac-Moody groups and their flag manifolds are rational formal, we also determine their rational homotopy groups and rational homotopy types.

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Zhao Xu-an, Jin Chunhua, Zhang Jimin. 2013-01-12. Poincaré series and rational cohomology rings of Kac-Moody groups and their flag manifolds. https://arxiv.org/abs/1301.2647

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