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arXiv · 1411.6594

Hirzebruch class and Bialynicki-Birula decomposition

Andrzej Weber
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Abstract

Suppose an algebraic torus acts on a complex algebraic variety $X$. Then a great part of information about global invariants of $X$ are encoded in some data localized around the fixed points. The goal of this note is to present a connection between two approaches to localization for $C^*$-action. The homological results are related to $S^1$-action, while from $R^*_{>0}$-action we obtain a geometric decomposition. We study the resulting decompositions of Hirzebruch $\chi_y$-genus and their relative versions. We show that via a limit process the second decomposition is obtained from the first one. The results are also valid for singular varieties.

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Andrzej Weber. 2014-11-24. Hirzebruch class and Bialynicki-Birula decomposition. https://arxiv.org/abs/1411.6594

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