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arXiv · 2507.21415

Equivariant Localization of $K$-homological Euler Class for almost connected Lie Groups

Hongzhi Liu·Hang Wang·Zijing Wang·Shaocong Xiang
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Abstract

Using the Witten deformation and localization algebra techniques, we compute the $G$-equivariant $K$-homology class of the de Rham operator on a proper cocompact $G$-spin manifold, where $G$ is an almost connected Lie group. By applying a $G$-invariant Morse-Bott perturbation, this class is localized near the zero set of the perturbation and can be identified explicitly with an element in the representation rings associated to some isotropy subgroups. The result yields an equivariant Poincar\'e-Hopf formula and supplies concise tools for equivariant index computations.

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Hongzhi Liu, Hang Wang, Zijing Wang, Shaocong Xiang. 2025-07-29. Equivariant Localization of $K$-homological Euler Class for almost connected Lie Groups. https://arxiv.org/abs/2507.21415

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