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arXiv · 2012.00199

A distinguished subring of the Chow ring and cohomology of $BPGL_n$

Xing Gu
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Abstract

We determine a subring of the Chow ring and the cohomology of $BPGL_n$, the classifying space of the projective linear group of degree $n$ over complex numbers, and explain a way in which this computation might play a role in the period-index problem. In addition, we show that the Chow ring of $BPGL_n$ is not generated by the Chern classes of linear representations of $PGL_n$.

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Xing Gu. 2020-12-01. A distinguished subring of the Chow ring and cohomology of $BPGL_n$. https://arxiv.org/abs/2012.00199

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