English

Equivariant maps between representation spheres

Algebraic Topology 2018-01-09 v2

Abstract

Let GG be a compact Lie group. We prove that if VV and WW are orthogonal GG-representations such that VG=WG={0}V^G=W^G=\{0\}, then a GG-equivariant map S(V)S(W)S(V) \to S(W) exists provided that dimVHdimWH\dim V^H \leq \dim W^H for any closed subgroup HGH\subseteq G. This result is complemented by a reinterpretation in terms of divisibility of certain Euler classes when GG is a torus.

Keywords

Cite

@article{arxiv.1704.01656,
  title  = {Equivariant maps between representation spheres},
  author = {Zbigniew Błaszczyk and Wacław Marzantowicz and Mahender Singh},
  journal= {arXiv preprint arXiv:1704.01656},
  year   = {2018}
}

Comments

The previous Subsection 4.1 and Section 5 are removed, as they relied on a false result from another paper: it is not true that the localization of the integral cohomology ring of the classifying space of $G = (\mathbb{S}^1)^k \times (\mathbb{Z}_p)^l$ with respect to the set of Euler classes of complex $G$-representations without a trivial direct summand is non-zero. 10 pages, no figures

R2 v1 2026-06-22T19:09:13.362Z