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arXiv · 2502.00956

$RO(C_2\times C_2)$-graded cohomology ring of a point and applications

Bill Deng·Mircea Voineagu
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Abstract

We describe the main properties of the $RO(C_2\times \Sigma_2)$-graded cohomology ring of a point and apply the results to compute the subring of motivic classes given by the Bredon motivic cohomology of real numbers and to compute $RO(C_2\times \Sigma_2)$-graded cohomology ring of $E_{\Sigma_2}C_2$. This generalizes Voevodsky's identification of motivic cohomology of real numbers with the positive cone of $RO(C_2)$ graded cohomology of a point.

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BibTeXRIS

Bill Deng, Mircea Voineagu. 2025-02-02. $RO(C_2\times C_2)$-graded cohomology ring of a point and applications. https://arxiv.org/abs/2502.00956

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