English

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

Operator Algebras 2025-08-22 v2 Functional Analysis K-Theory and Homology

Abstract

Using the Witten deformation and localization algebra techniques, we compute the GG-equivariant KK-homology class of the de Rham operator on a proper cocompact GG-spin manifold, where GG is an almost connected Lie group. By applying a GG-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.

Keywords

Cite

@article{arxiv.2507.21415,
  title  = {Equivariant Localization of $K$-homological Euler Class for almost connected Lie Groups},
  author = {Hongzhi Liu and Hang Wang and Zijing Wang and Shaocong Xiang},
  journal= {arXiv preprint arXiv:2507.21415},
  year   = {2025}
}