Multivalued sections and self-maps of sphere bundles

M. C. Crabb

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arXiv · 2208.09637

Multivalued sections and self-maps of sphere bundles

M. C. Crabb

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Abstract

Let $G$ be a finite group and $V$ a finite dimensional (non-zero) orthogonal $G$-module such that, for each prime $p$ dividing the order of $G$, the subspace of $V$ fixed by a Sylow $p$-subgroup of $G$ is non-zero and, if the dimension of $V$ is odd, has dimension greater than $1$. Using ideas of Avvakumov, Karasev, Kudrya and Skopenkov and work of Noakes on self-maps of sphere bundles, we show that, for any principal $G$-bundle $P\to X$ over a compact ENR $X$, there exists a $G$-map from $P$ to the unit sphere $S(V)$ in $V$.

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M. C. Crabb. 2022-08-20. Multivalued sections and self-maps of sphere bundles. https://arxiv.org/abs/2208.09637

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