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arXiv · 1708.08532

Two remarks on Wall's D2 problem

Ian Hambleton
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Abstract

If a finite group $G$ is isomorphic to a subgroup of $SO(3)$, then $G$ has the D2-property. Let $X$ be a finite complex satisfying Wall's D2-conditions. If $π_1(X)=G$ is finite, and $χ(X) \geq 1-Def(G)$, then $X \vee S^2$ is simple homotopy equivalent to a finite $2$-complex, whose simple homotopy type depends only on $G$ and $χ(X)$.

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Ian Hambleton. 2017-08-28. Two remarks on Wall's D2 problem. https://doi.org/10.1017/s0305004118000385

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