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arXiv · 2411.06570

Virtual Localisation Formula for $ SL_{\eta} $-Oriented Theories

Alessandro D'Angelo
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Abstract

In this paper, we extend the Virtual Localization Formula of Levine to a wide class of motivic ring spectra, obtaining in particular a localization formula for virtual fundamental classes in Witt theory $ \mathrm{KW} $. Applying standard tools of $\mathbb A^1$-intersection theory to any $ SL_{\eta} $-oriented spectra $ \mathrm A $, we obtain an additive presentation of $ \mathrm A(BN) $, for $ N $ the normaliser of the torus in $ SL_2 $. Then we establish an equivariant Atiyah-Bott localization theorem for $ \mathrm A_N^{\mathrm{BM}}(X) $ and we conclude with the $N$-equivariant virtual localisation formula. Of independent interest, we also describe the ring structure of $ \mathrm{KW}(BN) $.

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Alessandro D'Angelo. 2024-11-10. Virtual Localisation Formula for $ SL_{\eta} $-Oriented Theories. https://arxiv.org/abs/2411.06570

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