On the Brown-Peterson cohomology of $BPU_n$ in lower dimensions and the Thom map

Xing Gu

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arXiv · 2005.03107

On the Brown-Peterson cohomology of $BPU_n$ in lower dimensions and the Thom map

Xing Gu

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Abstract

For an odd prime $p$, we study the image of the Thom map from Brown-Peterson cohomology of $BPU_n$ to the ordinary cohomology in dimensions $0\leq i\leq 2p+2$, where $BPU_n$ is the classifying space of the projective unitary group $PU_n$. Also we show that a family of well understood $p$-torsion cohomology classes $y_{p,k}\in H^{2p^{k+1}+2}(BPU_n;Z_{(p)})$ are in the image of the Thom map.

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Xing Gu. 2020-05-06. On the Brown-Peterson cohomology of $BPU_n$ in lower dimensions and the Thom map. https://arxiv.org/abs/2005.03107

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